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Tumor-associated macrophages (TAMs), the main components of infiltrating leukocytes in tumors, often play a key role in promoting cancer development and progression. The tumor-specific microenvironment forces the phenotype of tumor-infiltrating to evolve in a direction favorable to tumor development, that is, the generation of M2-like TAMs. Consequently, the dual intervention of cancer cells and tumor microenvironment has become a research hotspot in the field of tumor immunotherapy. In this contribution, we developed pH-sensitive mesoporous calcium silicate nanocomposites (MCNs) encapsulated with indocyanine green (ICG) to enable the effective combination of photothermal therapy (PTT) and photodynamic therapy (PDT) triggered by the 808 nm near-infrared (NIR) light. The mannose and hyaluronic acid-grafted MCNs specifically targeted TAMs and tumor cells and promoted cell apoptosis both in vitro and in vivo. This paper revealed that irradiation of ICG loaded MCNs with NIR can produce a potent hyperthermia and induce abundant intracellular singlet oxygen generation in the target cells. These results suggest that the novel nanoplatform is believed to facilitate the delivery of chemotherapeutic agents to the tumor microenvironment (TME) to enhance the effects of tumor treatment.

In the present work, thermal exposure was performed on the 7B50-T7451 aluminium alloy friction stir welding (FSW) joints at different temperatures (150 °C, 175 °C and 220 °C) for 200h. The results show that the microstructure and mechanical properties of as-welded joints along the thickness direction of the plate are heterogeneous. The hardness and strength of FSW joints decrease while the elongation continuously increases with increasing thermal exposure temperature. Compared with the base material, the joints present much higher hardening capacity which is further increased with increasing temperature. The precipitates in the heat-affected zone (HAZ) exhibit continuous coarsening and the precipitate distribution becomes broader as the temperature rises. The transformation from η' phase to η phase is obvious at 220 °C. The weld nugget zone (WNZ) re-precipitates a large number of nano-scale η particles subjected to 200h thermal exposure at 150 °C and re-precipitated η phase in WNZ of the double-sided joint has reached micron-sized at 175 °C and 220 °C. When exposed at different temperatures, all FSW joints show typical ductile fracture features. Fracture positions at different thermal exposure temperatures are inconsistent and this variation is closely related to different microstructural characteristics.

Heterogeneous rectangular welded tube has serious anisotropy of parent metal and weld zone, in order to improve the prediction accuracy of cross-section deformation of tube in rotary draw bending (RDB), it is necessary to select the appropriate yield criterion to describe the anisotropic characteristics of heterogeneous rectangular welded tube. So the anisotropic parameters of Hill’48 and Barlat’89 yield criteria of parent and weld zone were obtained by using the digital image correlation test, then FE models of RDB of rectangular welded tube using different yield criteria were established. Based on these established FE models, the cross section deformation of thin-walled heterogeneous rectangular welded tube in RDB considering different yield criteria was researched. The results showed that, for the height and width deformation ratio of rectangular welded tube, the simulated results obtained by Mises, Barlat’89 and Hill’48 yield criteria in sequence, gradually increased to experimental results, this indicated that Hill’48 can well describe the anisotropic characteristic of rectangular welded tube. Further, under the condition of different bending angles and different core numbers, the maximum height deformation ratio obtained by Mises, Barlat’89 and Hill’48, successively, gradually increased to experimental results, which meant that Hill’48 anisotropic yield criterion was the most suitable one to predict cross section deformation of QSTE700 rectangular welded tube in RDB.

The bent double-ridged rectangular tube (DRRT) with high forming quality is helpful to improve the microwave transmission accuracy. For reducing the cross-sectional deformation in the H-typed bending process, in addition to using rigid mandrel to support the inside of tube, ridge groove fillers are also added to restrict the deformation of ridge grooves. Because of the change of stress and strain state of bent tube in bending, rigid mandrel retracting and specially twice-springback stages, and the springback of fillers, the cross-sectional deformation of tube in each stage may be different. Therefore, based on the ABAQUS platform, the finite element models (FEM) for H-typed bending, mandrel retracting and twice-springback stages of H96 DRRT with fillers were established and validated. It is found that, for the height and width deformation of tube and spacing deformation of ridge grooves, retraction of mandrel can make the distribution of these deformations more uniform along the bending direction. The first springback can reduce these deformations significantly, which should be emphasized. But the second springback only increases them by less amount, which can be ignored. The smaller height deformation of ridge groove and filler can be neglected.

Different yield criterion has great difference in predicting the deformation of tube with different material. In order to improve the prediction accuracy of the cross-sectional deformation of the double-ridged rectangular tube (DRRT) during rotary draw bending (RDB) process, Mises isotropic yield criterion, Hill’48 and Barlat/Lian anisotropic yield criteria commonly used in practical engineering are introduced to simulate RDB of DRRT. The inverse method combining uniaxial tensile test of whole tube and response surface methodology was proposed to identify the parameters of Hill’48 and Barlat/Lian yield criteria of small-sized H96 brass extrusion DRRT as well. Then based on ABAQUS/Explicit platform, the FE models of RDB process of DRRT considering Mises, Hill’48 and Barlat/Lian yield criteria were built. The results show that: The variation trend of cross-sectional deformation ratio is same when using different yield criteria. The cross-sectional deformation ratio by using Mises yield criterion is close to that by using Hill’48 yield criterion. However, there is a quite difference between by using Barlat/Lian yield criterion and by using Mises or Hill’48 yield criteria. The prediction values of cross-sectional height deformation by using three yield criteria all underestimate the experiment ones, and the prediction values of cross-sectional width deformation overestimate the experiment ones. By comparing the simulation results of cross-sectional deformation of the DRRT with different yield criteria and experiment ones, Barlat/Lian yield criterion is found to be suitable for describing the RDB process of DRRT.

Rheumatoid arthritis (RA) is a chronic inflammatory disorder characterized by destructive polyarthritis and systemic complications. It increases cardiovascular morbidity and mortality. However, the mechanism underlying RA-related cardiac damage remains largely unknown. Here, we found and characterized a non-human primate (NHP) model with spontaneous RA similar to the human conditions. Compared with the control group, the cardiac function in RA monkeys showed progressively deterioration; histologically, we found significantly increased inflammatory cell infiltration, cell death, and fibrosis in RA monkey heart tissue. Mechanistically, the upregulated receptor-interacting protein kinase 1 (RIPK1) in RA monkey heart tissue bound to voltage-dependent anion-selective channel 1 (VDAC1), increased VDAC1 oligomerization, and subsequently induced cardiac cell death and functional impairment. These findings identified that RIPK1-VDAC1 pathway is a promising target to treat cardiac impairment in RA. This unique model of RA will provide a valuable tool for mechanistic and translational studies.

The stabilization of protein is crucial for its practical usage in industrial applications. This study sought to systematically determine how deep eutectic solvents (DESs) can stabilize proteins and affect their structure and activity by employing lysozyme as a model. Seven choline chloride (ChCl)-based DESs with polyols and sugars as hydrogen bond donors (HBDs) were evaluated as co-solvents at 10−75 wt% concentrations. The thermal stability (Tm) of lysozyme was improved by all DESs. The Tm increase had a positive correlation with the DES concentrations and the number of −OH groups in HBDs. Increased α-helical contents in all conditions partially support the protein stabilization by DESs. Lysozyme could maintain its native tertiary structure and activity at 10 wt% DESs. At higher concentrations, the polyol-class DESs yielded higher Tm and more structure compaction with lower activity suppression than the sugar-class solvents, which displayed discernable changes in their tertiary structure with possible binding at the active site of lysozyme. The hydrogen-bonding ability of HBDs was suggested to play a key role in both classes of DESs by increasing the hydrogen bond network around the protein, which could recruit a protective hydration layer and lead to structure compaction.

High-precision LAI (leaf area index) spatiotemporal data obtained from MODIS satellite remote sensing products are important for studying vegetation growth status, biomass carbon reserves, and the spatiotemporal dynamics of carbon cycling. LAI significantly influences biomass accumulation during the growth of bamboo forest in subtropical zones. Therefore, we applied the ensemble Kalman filter (EnKF) data assimilation algorithm to assimilate MODIS LAI products, and used assimilated LAI and the normalized difference vegetation index, enhanced vegetation index, simple ratio index as variables in the random forest model to estimate bamboo forest above ground biomass (AGB) in Zhejiang Province. Assimilated LAI spatiotemporal data using EnKF greatly improve the accuracy of MODIS LAI products, the R2 between assimilated and observed LAI was 0.92, and the RMSE was 0.37. Variations in the assimilated LAI time series were consistent with the seasonal dynamics of bamboo forest growth and had a significant effect on AGB. Moreover, the random forest model had strong predictive capabilities. A comparison of training and testing results produced accuracy (R) values for the random forest model using the assimilated LAI time series of 0.71 and 0.73, respectively. Using the assimilated LAI achieved a more accurate AGB estimate than using MODIS LAI time series products, as the R values were 54.3% and 58.7% higher, and the RMSE values were 19.2% and 19.1% lower for training and testing results, respectively. The calculated spatial distribution of bamboo forest AGB in Zhejiang province was consistent with the observed values. By combining assimilation technology of the MODIS LAI time series with the random forest model to more accurately estimate bamboo forest AGB in Zhejiang province, this study provided a new method for estimating large scale forest AGB based on low-resolution time series data.

Using a panel data of China's OFDI over the period of 2003–2013, this study investigates how cultural distance and its dimensions explain China's OFDI spatial differentiation. We find that cultural distance has a curvilinear (U-shaped) relationship with China's OFDI. The growth rates of “liability of foreignness (LOF)” and “advantages of foreignness” (AOF) finally determine whether cultural distance cause conflicts or improve innovation. In addition, we find that how China's OFDI activities are related to the difference of cultural distance hinges on the particular cultural dimension in question. The latter suggests that that the relative weight of cultural dimensions should be considered in the calculation of cultural distance. Overall, this study makes important contributions to both theory and practice. Our findings offer important insights into OFDI activities and provide guidelines for managers about entry strategies.

This paper develops a comprehensive further research on the springback of rotary draw bending (RDB) of rectangular H96 tube, based on the review and revise of the previous research work. The effects of process conditions to springback and sectional deformation are studied and compared by using the simulation and the sensitivity analysis mathematical model. The coupling effects between springback and sectional deformation in the bending process are revealed by using the simulation and the theoretical analysis model. The theoretical analysis model of springback angle is established by taking sectional deformation into consideration in term of piecewise functions of sectional shape. Finally, how to control springback under different filler conditions is studied. The accuracy of finite element (FE) simulation has an important impact on this study, thus it is improved from two aspects of FE modeling, i.e. the accurate descriptions of the boundary conditions and the material constitutive model. The material constitutive model considers the varied elastic modulus effect and the Bauschinger effect. Research shows that: (1) the boundary conditions of force loading dies and tube fillers are the main factors influencing springback and sectional deformation; (2) the sectional deformation is more sensitive to process parameters than the springback; (3) the springback has great effect on the decrease of section sagging and longitudinal section ovalization; (4) the amount of springback is increasing as the overall deformation increases; (5) if the tube filler is mandrel-cores die, the optimized parameters combinations of pressure die can be used to reduce both the springback and the sectional deformation.

Rigid mandrel plays an important role in restricting the cross-sectional deformation of double-ridged rectangular tube in rotary draw bending. So a 3D FE model of H-typed rotary draw bending of the tube was established, and the influence law of rigid mandrel parameters on cross-sectional deformation was obtained. With the increase of core number, the deformation of different parts of tube decreases. When core number exceeds 3, the effect of increasing the core on the improvement of cross sectional deformation is insignificant. A curved mandrel with simple structure was proposed, and the effect of curved mandrel on controlling of cross-sectional deformation is better than that of separated rigid mandrel.

Adding a filler to the inner ridge groove has been considered to reduce the inevitable cross-sectional deformation of double-ridged rectangular bent tube during E-typed rotary draw bending process. Using a numerical simulation method, the three-dimensional finite element models for E-typed rotary draw bending of H96 brass double-ridged rectangular tube without and with inner ridge groove filler under different bending radii were established. Based on the models, it is found that using the filler can obviously reduce the width deformation of inner ridge groove and the good double-ridged rectangular bent tube with small bending radius can be obtained. These results have engineering application worth for improving the forming quality of double-ridged rectangular bent tube.

NiTiNb is a wide-hysteresis shape memory alloy, and the microstructure directly affects the shape memory properties. In this study, the microstructures and shape memory properties of hot-forged NiTiNb alloys were tailored by multi-pass equal-channel angular pressing (ECAP) at high temperatures. First, grain refinement structures with severely deformed grains and fully dynamic recrystallized equiaxed grains were prepared by ECAP at 650 °C and 800 °C (denoted as ECAP-650 and ECAP-800, respectively). The correlation between the two types of ECAP-based microstructures and shape memory properties of the NiTiNb alloy was established. The results indicated that there was no direct relationship between the grain size and thermally induced martensite (TIM) transformation. However, the dislocations in the deformed grains hindered the TIM transformation, resulting in a lower martensite transformation temperature. The greater β-Nb deformation during the stress-induced martensite (SIM) increased the martensite transformation hysteresis of the ECAP-processed samples. Simultaneously, the recrystallized grains were more beneficial to the stability of the SIM. Compared with the initial sample, the transformation hysteresis temperatures of the ECAP-650 and ECAP-800 samples increased by 29 °C and 34 °C, respectively. The refined grains were not conducive to the recovery of transformation strain, but they were beneficial for increasing the recovery stress. Compared to the initial sample, the recoverable transformation strain of the ECAP-650 and ECAP-800 samples decreased by 18.3% and 6.6%, respectively, and the corresponding maximum recovery stresses increased by 23.7% and 12.2%. Similar to the recovery stress, the thermomechanical cyclic stability of the ECAP-processed samples was also improved because the dislocation content introduced by lattice mismatch was reduced, and the sample with deformed grains had better stability than the sample with recrystallized grains.

Cross sectional deformation of double-ridged waveguide tube easily occurs in rotary draw bending due to its structural features of hollowness, thin-wall and shape complexity. Particularly, the ridge grooves deformation would largely affect the transmission characteristics of double-ridged waveguide tube. Thus, using plasticity deformation theory, an analytical method to investigate the ridge grooves deformation is proposed, in which the ridge grooves deformation is considered to be resulted from three parts of deformation, including flange sagging, web deflection and variation of flange width. Then, the analytical method is verified by a FE model from various viewpoints. Finally, the contribution of every part to the ridge grooves deformation under different conditions is analyzed combining analytical and simulative methods. The results show that: (1) The contribution of flange sagging to the width deformation of outer and inner ridge grooves is usually far small and can be omitted. The web deflection results in the decrease of width deformation of outer ridge groove, but the variation of flange width increases that. The web deflection and variation of flange width all lead to the increase of width deformation of inner ridge groove. (2) With the increase of bending angle, the width deformation of outer ridge groove changes little while the absolute value of width deformation of inner ridge groove increases. When the bending radius decreases, the absolute value of width deformation of outer and inner ridge grooves all increase. With the increase of core number, the width deformation of outer ridge groove changes from shrinking to widening while there is no change for the width deformation of inner ridge groove.

Wrinkling of QSTE700 high strength steel thin-walled rectangular welded tube is easy to occur in rotary draw bending (RDB) process due to the existence of non-homogeneous weld zone and corner with cold bending effect. So the FE model of RDB of QSTE700 rectangular welded tube considering weld zone and corner with cold bending effect was established. Based on this FE model, the effect of weld zone and corner with cold bending effect on wrinkling of inner flange and side wall of rectangular welded tube in RDB was researched. The results showed that: when weld zone and corner with cold bending effect were studied separately, weld zone both increased the wrinkling height of inner flange and side wall. However, the influence of corner with cold bending effect on wrinkling height of side wall and inner flange was inconsistent, it reduced the wrinkling height of inner flange, but increased the wrinkling height of side wall. When the weld zone and corner interacted, the coupling effect between weld zone and corner with cold bending effect on wrinkling resulted in the decrease of wrinkling height of inner flange and increase of wrinkling height of side wall of rectangular welded tube in RDB.

We have investigated the micro-bubbles generated by laser induction on an individual carbon nanocoil (CNC) immerged in deionized water. The photon energy of the incident focused laser beam is absorbed by CNC and converted to thermal energy, which efficiently vaporizes the surrounding water, and subsequently a micro-bubble is generated at the laser location. The dynamics behavior of bubble generation, including its nucleation, expansion and steady-state, has been studied experimentally and theoretically. We have derived equations to analyze the expansion process of a bubble based on classical heat and mass transfer theories. The conclusion is in good agreement with the experiment. CNC, which acts as a realistic micro-bubble generator, can be operated easily and flexibly.

Renal cell carcinoma (RCC) with rhabdoid differentiation is a recently described variant of RCC, which has seldom been reported in China. This form of differentiation has been generally associated with a poor prognosis and is often present in tumors with a poorly differentiated morphology. The development of a rhabdoid morphology appears to represent a common dedifferentiation pathway for renal parenchymal malignancies. The aim of this study is to evaluate the incidence and clinicopathologic features of RCC rhabdoid differentiation in Chinese adult patients and to further investigate its origin. We reviewed 723 cases of RCC obtained between January 2012 and March 2014 in Peking University First Hospital. From these cases, 10 (1.4%) were found to have areas of classic rhabdoid morphology. Immunohistochemistry for vimentin, cytokeratin (CK) (pan-cytokeratin (AE1/AE3), CK20, CK5/6, CK7, and CK8/18), RCC, CD10, Pax-2, Pax-8, CD117, desmin, muscle-specific actin, CD68, p53, and Ki-67 was performed in each case using the labeled streptavidin-biotin method. Rhabdoid differentiation was identified in association with clear cell RCC, papillary RCC (II type), and sarcomatoid RCC. We compared the morphologic and immunohistochemical features between rhabdoid and nonrhabdoid components. In our cases, rhabdoid differentiation was characterized by the presence of cohesive large epithelioid cells with abundant pink cytoplasm and central eosinophilic intracytoplasmic inclusions and 1 or more large, oval, eccentric, or irregular nuclei containing prominent nucleoli. Most of the rhabdoid areas showed a solid growth pattern. In our series, RCC with rhabdoid differentiation had an aggressive biological behavior, and rhabdoid components were most likely associated with high-grade tumors of advanced stage. In all cases, the rhabdoid and nonrhabdoid tumoral areas without sarcomatoid differentiation exhibited the very similar immunophenotype as follows: vimentin (+/-), AE1/AE3 (+), CK8/18(+), CK7(+/-), CK5/6 (-), CK20 (-), RCC (focal +), CD10 (focal +), Pax-2 (+), Pax-8 (+), CD117 (+/-), desmin (-), muscle-specific actin (-), and CD68 (-). On p53 and Ki-67 immunohistochemistry, the positive rate of rhabdoid cells for both p53 and Ki-67, similar to sarcomatoid cells, was higher than that of nonrhabdoid tumor cells without sarcomatoid differentiation. Our results indicate that the incidence rate of rhabdoid differentiation in Chinese adult RCC patients is lower than that of foreign reports. We support that the rhabdoid and nonrhabdoid tumor cells originate from the same clone, and the rhabdoid components present high proliferative activity and indicate a poor prognosis.

A Lifeguarding Operational Camera Kiosk System (LOCKS) is developed and implemented at the North Beach of Port Washington, WI to provide real-time flash rip warnings to beach users for the first time. LOCKS has three components. First, a real-time environmental observation system acquires timely beach view images and local environmental condition data. Second, an integrated nowcast forecast operational system, a high performance and distributed computing infrastructure, digitally detects and assesses flash rip hazards in high, moderate or low risks. Third, an automated kiosk dynamically issues real-time warnings on site by a three-color dynamic lights and a digital display monitor. Results of flash rip detection show that the combined length threshold and HSV-based segmentation method can be used in both sunny and cloudy days with an overall accuracy of 83%. Nonstationary locations and intermittent occurrences of flash rips are observed and characterized. The length of the flash rip ranges between 10 and 50 m. The duration of flash rips varies from 1 to 5 min with 65% of flash rips less than 2 min. A flash rip occurrence checklist by adding two new (storm and visual observation) factors is constructed to reliably assesses the likelihood of hazardous flash rips. Public communication through media mentions, news releases, and website usages show the strong interest and support of the LOCKS as a new approach to issue timely and dynamic flash rip warnings to beach users. LOCKS can be used to issue warnings of other types of rips like bathymetry-controlled and boundary-controlled rip currents in the future.

Mucopolysaccharidosis VII (MPS VII) is due to the deficient activity of β-glucuronidase (GUSB) and results in the accumulation of glycosaminoglycans (GAGs) in lysosomes and multisystemic disease with cardiovascular manifestations. The goal here was to determine the pathogenesis of mitral valve (MV) disease in MPS VII dogs. Untreated MPS VII dogs had a marked reduction in the histochemical signal for structurally-intact collagen in the MV at 6 months of age, when mitral regurgitation had developed. Electron microscopy demonstrated that collagen fibrils were of normal diameter, but failed to align into large parallel arrays. mRNA analysis demonstrated a modest reduction in the expression of genes that encode collagen or collagen-associated proteins such as the proteoglycan decorin which helps collagen fibrils assemble, and a marked increase for genes that encode proteases such as cathepsins. Indeed, enzyme activity for cathepsin B (CtsB) was 19-fold normal. MPS VII dogs that received neonatal intravenous injection of a gamma retroviral vector had an improved signal for structurally-intact collagen, and reduced CtsB activity relative to that seen in untreated MPS VII dogs. We conclude that MR in untreated MPS VII dogs was likely due to abnormalities in MV collagen structure. This could be due to upregulation of enzymes that degrade collagen or collagen-associated proteins, to the accumulation of GAGs that compete with proteoglycans such as decorin for binding to collagen, or to other causes. Further delineation of the etiology of abnormal collagen structure may lead to treatments that improve biomechanical properties of the MV and other tissues.

A new type of mandrel, which is PVC material and supposed as elastic–plastic deformable part in the simulation, is proposed to use in rotary-draw bending process, due to it can fill the tube entirely. The effect of PVC mandrel on the forming quality of rectangular H96 tube, such as tube damage distribution, wall thickness variation, section deformation, springback, is researched by comparing with the traditional mandrel-cores die. It is found that, the maximum damage value obtained with PVC mandrel is smaller than that with mandrel-cores die. The PVC mandrel leads to a smaller tube thickness variation and a more uniform tube thickness distribution compared with the mandrel-cores, for the PVC mandrel brings about smaller stress in the bending process. The PVC mandrel is recommended to be used in the rotary-draw bending process due to its advantage in the prevention of height deformation, though, the constraint effect on the tube width provided by the PVC mandrel is a little weaker than that by mandrel-cores die. Especially, the PVC mandrel with 1.5 times plastic hardening performs excellent well on the reduction of sectional height deformation of symmetrical line. The springback angle obtained with mandrel-cores die is smaller due to the retracting mandrel process. The PVC mandrel should be taken away from the tube before the springback occurs, which can be realized by heating the mandrel to soft.

Mucopolysaccharidosis VII (MPS VII) is due to deficient activity of the lysosomal enzyme β-glucuronidase (GUSB) and results in the accumulation of glycosaminoglycans (GAGs). This study determined the long-term effect of neonatal intravenous injection of a gamma retroviral vector (RV) on cardiac valve disease in MPS VII dogs. Transduced hepatocytes secreted GUSB into the blood for up to 11 years at levels similar to or greater than those achieved with enzyme replacement therapy (ERT). Valve regurgitation and thickening were scored from 0 (normal) to +4 (severely abnormal). At 1 year, untreated MPS VII dogs had mitral regurgitation, mitral valve thickening, aortic regurgitation, and aortic valve thickening scores of 2.3 ± 0.7, 2.3 ± 0.6, 1.8 ± 0.5, and 1.6 ± 0.7, respectively, which were higher than the values of 0.6 ± 0.1, 0.1 ± 0.4, 0.3 ± 0.8, and 0.1 ± 0.4, respectively, in treated MPS VII dogs. Treated MPS VII dogs maintained low aortic regurgitation and aortic valve thickening scores in their lifetime. Although mitral regurgitation and mitral valve thickening scores increased to 2.0 at ≥ 8 years of age in the treated MPS VII dogs, older normal dogs from the colony had similar scores, making it difficult to assess mitral valve disease. Older treated dogs had calcification within the mitral and the aortic valve annulus, while GUSB staining demonstrated enzyme activity within the mitral valve. We conclude that neonatal RV-mediated gene therapy reduced cardiac valve disease in MPS VII dogs for up to 11 years, and propose that neonatal initiation of ERT should have a similar effect.

Based on the isotropic-hardening model, mixed-hardening model and Yoshida–Uemori two-surface model, the accuracy of springback prediction, such as section sag after springback, springback radius and springback angles, is researched for rotary-draw bending of thin-walled rectangular H96 tube to achieve a high precision of springback prediction. The material parameters of the three hardening models are obtained from the tensile and tension–compression tests of rectangular H96 tube specimen. The results show that, due to the tube undergoes reverse loading path in the bending process, and the Yoshida–Uemori model can well describe the transient Bauschinger effect and permanent softening of reverse loading, the Yoshida–Uemori model is more suitable for springback angle prediction than the other two hardening models, especially for the springback prediction with large deformation. Its average error is only 5.18%. The Yoshida–Uemori model also performs better on the prediction of section sag after springback, but the advantage is not obvious, and all of the three hardening models can accurately predict the springback radius with the average errors even smaller than 2.60%. It is also found the occurrence of tube reverse loading depends on the mandrel die, so if the tube is filled by the PVC mandrel, the three hardening models almost obtain the same prediction results; the filler of the tube determines whether the Yoshida–Uemori model should be considered.

Inner flange and side wrinkling often occur in rotary-draw bending process of rectangular aluminum alloy wave-guide tubes, and the distribution and magnitude of wrinkling is related to geometrical parameters of the tubes. In order to study the effects of geometrical parameters on wrinkling of rectangular wave-guide tubes, a 3D-FE model for rotary-draw bending processes of thin-walled rectangular aluminum alloy wave-guide tubes was built based on the platform of ABAQUS/Explicit, and its reliability was validated by experiments. Simulation and analysis of the influence laws of geometrical parameters on the wave heights of inner flange and side wrinkling were then carried out. The results show that inner flange wrinkling is the main wrinkling way to rectangular wave-guide tubes in rotary-draw bending processes, but side wrinkling cannot be neglected because side wrinkling is 2/3 of inner flange wrinkling when b and h are smaller. Inner flange and side wrinkling increase with increasing b and h; the influence of b on side wrinkling is larger than that of h, while both b and h affect inner flange wrinkling greatly. Inner flange and side wrinkling decrease with increasing R/h; the influence of h on inner flange and side wrinkling is larger than that of R.

The accuracy for cold-bending springback prediction is determined by the sensitivity and accuracy of the material constitutive model. Thus, the material constitutive model is developed and improved by many researchers, and the improved models are applied in the springback calculation with various materials in finite element simulation or theoretical analysis. To provide a reference for the researchers studying cold-bending springback problems, a review of the development and application of the material constitutive models is presented in this paper, which conducts from the elastic behavior, the anisotropy, and the work-hardening. It can be summarized as: (1) Springback prediction result is higher and more accurate when the variable elastic modulus and the nonlinear recovery are considered. (2) The isotropic hardening leads to an overestimation of the springback, which can be avoided by a hardening model describing the Bauschinger effect. (3) The hardening model has greater impact on springback than the yield criterion. (4) Good accuracy of the springback prediction can be achieved when the variable elastic modulus effect, the material anisotropy and the nonlinear hardening are considered together. It is also found the theory development and practical application of the material constitutive models are out of line, due to lacking further experiment, or that the stress loading–reloading history within a bending part may be not so complex as that “ratchetting behavior” discussed.

In order to study the effects of the process parameters on springback and section deformation, a sensitivity analysis model was established based on the combination use of the multi-parameter sensitivity analysis method and the springback/section deformation prediction finite element model, and by using this model the sensitivities of the springback and the section deformation to process parameters were analyzed and compared. The results show that the most sensitive process conditions for springback angle are the boost speed and the pressure of pressure die, and the most sensitive process condition for section deformation is the number of cores. When the clamp force, the boost speed and the pressure of pressure die are utilized to control section deformation, the effect of these process parameters on springback should be considered. When the process parameters are mainly used to control springback, the effect of these process parameters on the section deformation should be always considered.

The rotary-draw bending process for thin-walled rectangular tube of aluminum alloy may produce a wrinkling phenomenon if processing parameters are inappropriate, especially for tubes with thin wall and small bending radius. To predict this wrinkling rule rapidly and accurately, here, a wrinkling wave function was proposed and a wrinkling prediction model was developed based on the deformation theory of plasticity combined with the energy method, and then the minimum bending radius without the occurrence of wrinkling in the process was obtained. Furthermore, the effects of geometrical parameters and the material properties of the tube on the minimum bending radius were analyzed. The results show that larger thickness-to-width ratio ( t / b ) and thickness-to-height ratio ( t / h ) are beneficial to improve the wrinkling limit of the tube. The minimum bending radius becomes smaller with an increase in strain-hardening exponent of the tube, whereas with the strength coefficient decreasing. And the Young's modulus has little effect on the wrinkling limit. These achievements are helpful to develop the bending technique and provide a guideline in rotary-draw bending process for thin-walled rectangular aluminum alloy tube.

Guided by experimentally observed solvolysis rates, 66 different reactivity indicators for predicting the quality of organic leaving groups are tested. None of these indicators is completely satisfactory. Most of the proposed indicators work well when the leaving group is a halogen, but poorly in the other cases (carboxylates, sulphates, phosphinates). This suggests that it is very difficult to devise simple reactivity indicators for the intrinsic quality of a leaving group, and supports recent work on molecule-dependent models for nucleofugality.

The cross-sectional distortion usually appears during rotary-draw bending process of thin-walled rectangular tube with small bending radius. To study the cross-sectional distortion of the tube, a three-dimensional finite-element model of the process was developed based on ABAQUS/Explicit code and its reliability was validated by experiment. Then, the cross-sectional distortion behaviors of the tube were investigated. The results show that a zone of larger circumferential stress appears on the tube when bending angle reaches 30°. And in the larger circumferential stress zone, the sagging phenomenon is produced obviously. The maximum cross-sectional distortion is located in the larger circumferential stress zone and the angle between the plane of maximum cross-sectional distortion and the bending reference plane is about 50°. The position of the maximum cross-sectional distortion keeps almost unchanged with the variation of the clearances between dies and tube.

To study whether the signaling pathway is activated in the inflammatory reaction of cerebral ischemia-reperfusion and its mechanism. The mice were randomly divided into sham group, ischemia-reperfusion group and TLR4-blocked group with different time points of reperfusion 12h, 24h, 48h and 72h group. We observed the different expression of TLR4 mRNA and MyD88 mRNA, activation of NF-kappaB and the TNF-alpha and IL-1beta protein levels in each group at different time point after ischemia-reperfusion. Mice cerebral ischemia was induced by occlusion of common carotid arteries (CCA) bilaterally. TLR4 signaling pathway could be inhibited by specific anti-TLR4 binding protein to prevent TLR4 from interacting with its receptors. We determined the result of TLR4 antibodies-blocking and mice cerebral ischemia-reperfusion injuries by Western blot, and evaluated neuronal damage in cortex. We also determined the expression of TLR4 mRNA and MyD88 mRNA by in situ hybridization (ISH), the activation of NF-kappaB by EMSA, and the expression of TNF-alpha protein by Western blot. Anti-TLR4 binding TLR4 receptors before reperfusion was effective; There was distinct difference among each group respecting neuronal damage; The expression of TLR4 mRNA and MyD88 mRNA, the activation of NF-kappaB, and the expression of TNF-alpha protein showed clear difference as well. LR4-mediated MyD88-dependent signaling pathway activated by ischemia-reperfusion may be involved in the mechanism of ischemia-reperfusion through upregulation of NF-kappaB and TNF-alpha.

According to the characteristics of the rotary-draw bending process of a thin-walled rectangular tube, a three-dimensional finite-elements model of this process is built under the ABAQUS/explicit environment based on the solution of several key techniques, such as contact boundary condition treating, material properties definition, meshing technology, etc. The actions of pressure die, wiper die, clamp die and mandrel are considered in the modeling process. Then the reliability of the model is validated by comparison with experiments in the literature. Furthermore, numerical simulation and analysis of the thin-walled rectangular tube bending process of 3A21 aluminum alloy have been carried out by using the model. The distribution laws of tangential stress in the process have been analyzed. The results show that the maximum tangential stress increases sharply in the initial stage and then keeps nearly constant with the progress of the bending process. The circumferential compressive stress zone is basically unchanged when the bending process becomes stable.

The splitting spinning which is designed to split a rotational disk blank into two flanges, is one of newly rising, green flexible forming technologies, and it can be widely applied to manufacture a whole pulley or wheel in fields of aerospace, automobile and train. The investigation of forming parameters influencing on splitting spinning force can provide the foundation for the choice of equipments, the design of dies and the determination of processing parameters. This paper aims at developing a reasonable formula between splitting spinning force and forming parameters by the principal stress method, and then the reliability of the formula is verified by the comparisons with experimental data. Meanwhile, both a reasonable method of calculating the three-dimensional projected areas and a more effective method of solving the average angle in the deformation zone are presented. Furthermore, based on the formula, the laws of initial thickness and initial diameter of workpiece, diameter and splitting angle of splitting roller and feed ratio of splitting spinning influencing on splitting spinning force are investigated. The achievements may serve as an important guide for the determination and optimization of forming parameters of splitting spinning.

In order to obtain the desired final shape, the blade precision forging requires a reasonable preformed billet which can be obtained from a given final shape by using backward tracing scheme based on FEM. The key technologies of backward tracing scheme based on 3D rigid-viscoplastic FEM were explored, and some valid algorithms or methods were proposed. A velocity field was generated by combining the direct iterative method with Newton-Raphson iterative method, and then the initial velocity field of backward tracing simulation was achieved by reversing the direction of the velocity field. A new method, namely the tracking-fitting-revising method, was proposed and can be used to determinate the criterion of separating a node from die in the backward tracing simulation. The ceasing criterion of the backward tracing simulation is that all the boundary nodes are detached from dies. Based on the above key technologies, the 3D backward tracing simulation system for the blade precision forging was developed, and its feasibility and reliability were verified by forward loading simulation.

We derive a correction term to the Fermi–Dirac energy for the system of N el noninteracting electrons confined to a cube with sides of infinite potential. This correction term is compared to one derived by Pauncz [R. Pauncz, Acta Physica Academiae Scientarium Hungaricae 1 (1952) 277]. Both models are compared to the exact quantum mechanical result with systems of 1 to 5000 electrons being considered. Agreement is seen to increase with particle number.

Mucopolysaccharidosis I (MPS I) due to deficient alpha-L-iduronidase (IDUA) activity results in accumulation of glycosaminoglycans in many cells. Gene therapy could program liver to secrete enzyme with mannose 6-phosphate (M6P), and enzyme in blood could be taken up by other cells via the M6P receptor. Newborn MPS I mice were injected with 10(9) (high dose) or 10(8) (low dose) transducing units/kg of a retroviral vector (RV) expressing canine IDUA. Most animals achieved stable expression of IDUA in serum at 1240 +/- 147 and 110 +/- 31 units/ml, respectively. At 8 months, untreated MPS I mice had aortic insufficiency, increased bone mineral density (BMD), and reduced responses to sound and light. In contrast, MPS I mice that received high-dose RV had normal echocardiograms, BMD, auditory-evoked brain-stem responses, and electroretinograms. This is the first report of complete correction of these clinical manifestations in any model of mucopolysaccharidosis. Biochemical and pathologic evaluation confirmed that storage was reduced in these organs. Mice that received low-dose RV and achieved 30 units/ml of serum IDUA activity had no or only partial improvement. We conclude that high-dose neonatal gene therapy with an RV reduces some major clinical manifestations of MPS I in mice, but low dose is less effective.

The development of aero-space, automobile, and high-technology industries requires the development of advanced plastic processing technologies in order to manufacture parts with light weight, high strength, high precision, high efficiency and at low cost, with a short period and a friendly environment, and with intellectualization and digitization. There are key problems urgently to be solved in the research and development of advanced plastic processing technologies, and FEM numerical simulation in combination with physical modeling and theoretical analysis has been playing a more and more important role in this field. This paper reports the state-of-the-art of some advanced plastic processing technologies and their numerical simulation in the authors’ laboratory, including the unequal deforming and in-plane bending process of strip metal, free deformation under dieless constraint and axial compressive precision forming process of tube, wrinkling and spring-back prediction and the NC bending precision forming process of thin-walled tubes, and precision forming laws and a complicated massive forming process such as blade forging with a damper platform.

A blade with a damper platform is one of the most important types of blades being developed in aeronautical engines. However, this type of blade is complicated in shape, consisting of four feature parts with different geometrical shapes. Besides obvious flow of material along the transverse direction, there is material flow along the longitudinal body during its forging process. In addition, the material used is difficult to deform. All these have a significant influence on the precision forging process of the blade. Thus, it is necessary to choose some feature sections along the transverse and longitudinal direction of blade and systematically understand the deformation characteristics of blade forging process. In this paper, by means of 3D rigid–viscoplastic FEM simulation of the precision forging process of the blade, the deformed meshes, distributions of some field variables, including velocity, effective strain, effective strain rate and effective stress are presented for the four chosen feature cross-sections and the velocity fields are obtained for a selected typical longitudinal feature section, and further the deformation characteristics of forging this blade have been revealed. This research may serve as a guide to the optimization design of the relevant processes and dies.

A blade with a damper platform, with excellent anti-vibration characteristics and high efficiency, has become one of the most important new types of blade being developed in the aeronautical engine. However, the blade is complicated in shape, and the material used for its manufacture is difficult to deform. Therefore, it is important to undertake research on the blade-oriented precision forging process using three-dimensional finite element method (3D FEM) method numerical simulation for the practice and the development of the process. However, up to now, literature on such research has been scant. In this paper, based on the rigid–viscoplastic principle, three-dimensional finite element simulation is reported for the isothermal precision forging of the blade using the penalty function, and eight-node hexahedral isoparameteric elements for discretizing the deforming workpiece and triangular elements for discretizing the die cavity. The method of contracting from the boundary to the interior, proposed by the authors, is used for remeshing a distorted mesh system, and the method of modifying the position of nodes touching the die according to its original normal, also proposed by the authors, is used to avoid the “dead lock” problem due to the normal uncontinuity of scatted die meshes, to enable the simulation to be successful. Friction is considered for the die–workpiece interface boundary condition, and an arc is considered for the tenon–body joint, and a damper platform–body joint on the blade die cavity, respectively, which make it possible for the simulation to approach the practical forging process of a blade with a damper platform. 3D FEM simulation results have been obtained for the initial and deformed configurations, the deformed meshes of typical cross-sections, the distribution of effective strain at the final stage, load–displacement curves, in this way the deformation law of the forging of a blade with a damper platform being revealed. The achievements of this research serve as a significant guide to the optimization of design for the relevant process and dies. The method used is also of general significance to the forging processes of other type of blades and other complicated massive deformation processes.

The influence of the shape and the initial position of the preform in precision forging of a compressor blade has been studied by 3D rigid–viscoplastic finite element method (FEM) in this paper. The results show the following: (1) a short and thick preform results in necking at the arc transition zone between the tenon and the blade body, and at the zone near the tip of the blade during deformation; (2) a long and slender preform produces bending in the middle of the blade body during deformation; (3) if a long and slender preform is bent in advance, an advisable product without flash can be obtained; (4) a reasonable initial position of the preform deviates to the thinner side of the blade die cavity; (5) this research is beneficial for the practice of the precision forging process of a compressor blade and it has a general significance for other types of blade.

Based on the rigid–viscoplastic principle, three-dimensional finite element simulation using the penalty function was performed for the isothermal forging of a compressor blade. The key technologies of 3D rigid–viscoplastic FEM simulation are introduced. The workpiece was discretized into eight-node hexahedral isoparameteric elements and the die cavity was discretized into triangular elements. The methods proposed by the authors to remesh the distorted mesh system and to modify a node touching the die have been used. By means of 3D FEM simulation of the compressor blade, the initial and deformed configurations, the deformed meshes of typical cross-sections, the contours of effective strain at the final stage, the vertical load–displacement curve for the upper die, and the horizontal load–displacement curves for the upper and lower dies have been obtained, and so the deformation law of compressor blade forging has been obtained. The research results show that the 3D rigid–viscoplastic FEM simulation system developed in this paper is practical and reliable. In the present simulation, the tenon and the body on the blade die cavity are joined by an arc which coordinates the deformation between the tenon and the body, and friction is considered along the interface between the die and the workpiece. Thus, this simulation approaches practical compressor blade forging. The computational results can also be applied effectively to other types of blade forging processes.

In order to inspect and analyze the deformation in the forging of a blade with a damper platform, a method of locally making a layer-built billet has been proposed, and physical modeling of the forging of a blade with a damper platform using plasticine has been carried out based on this method. By physical modeling of the forging of a blade with a damper platform, some basic flowing laws in the forging of a blade with the damper platform have been obtained. The simple and valid accomplishment of experiment shows that this method of a making billet is reasonable and practicable, and it can be popularized to the physical modeling of other components.

In this paper, the critical condition which is used to distinguish the deformation patterns between stretching and drawing has been advanced in accordance with the investigation of the compound-forming process of hemispherical parts. Also, the compound-degree equation expressed by the centre-line length of the cross-section of the parts is derived during the compound-forming of hemispherical parts in terms of the concept of the compound-degree proposed by the authors in this paper. This work will help in determining the properties of the procedure and ensuring the quality of the products.