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Even though the importance of public participation in urban planning has been thoroughly discussed in European and North American planning circles, it is still a new topic in China. Top-down planning processes are dominant in China, yet local officials are empowered to determine the extent and nature of public participation during local planning processes. To date, few scholars have explored how local decision-makers use this authority or which elements factor into the strategies they choose. Our analysis of master plans from 129 of China's county-level cities shows that the age, overseas education experiences, and professional experiences of local officials have a significant effect on their decisions related to promoting public participation during the planning process, while their education level, Party school experience, and political career experience do not. We conclude that older-age local officials with overseas study experience, or with a background in technology or academia, tend to have a greater interest in promoting public participation in the process of crafting local master plans. We finally conclude with three insights that aim to enhance public participation in urban planning and land use management policy making: (1) Increased international communications and specific empirical case studies of public participation for officials; (2) Standardization of public participation in the planning and management processes; and (3) Utilization of more user-friendly online resources to expand public involvement and highlight the potential benefits for officials. • Local CCP secretaries and mayors play a powerful role in promoting public participation in China's urban planning. • Local officials' interests in public participation for urban planning are positively affected by age, overseas and professional experiences. • The planning consultants had little effect on public participation involvement in urban planning in China. [ABSTRACT FROM AUTHOR]

A prediction model for the folding defect in transitional region during local loading forming of titanium alloy large-scale rib-web component was developed by the combination of finite element simulation, space-filling Maximin Latin hypercube designs method and back-propagation neural network. The FE model of local eigen model of transitional region during local loading forming of large-scale rib-web component was established based on DEFORM-2D and validated by physical experiment. The Maximin Latin hypercube designs method was applied to design uniform experimental schemes with geometrical conditions and reduction amounts as experimental variables. After simulations of the designed experiments, the back-propagation neural network was used to synthesize the data sets (results of folding defect). Finally, a prediction model was established for folding defect judgment in transitional region under various geometrical conditions and reduction amounts during local loading forming of large-scale rib-web components. The predicted results are quite consistent with the results obtained from FE simulation and experiment. [ABSTRACT FROM AUTHOR]

• The MAMD model of Ti2AlNb-based alloy B2 phase matrix was established. • The propagation behavior of microcracks in B2 matrix with different orientations was revealed by MD method. • Simulations and theoretical predictions result in consistent crack-tip behaviors. • Brittle fracture and ductile fracture exist simultaneously in the same material. The influence mechanism of crack orientation on B2 phase crack propagation behavior under cyclic loading is studied by using the meta-atom molecular dynamics (MAMD) method, and the simulation results are compared and verified based on the theory of linear elastic fracture mechanics. According to the different propagation speed of crack in B2 phase matrix, the crack propagation process can be divided into three stages: elastic stage, rapid propagation stage and slow propagation stage. The toughness or brittleness of the crack mainly depends on the competition between the cleavage fracture of the atomic bond and the plastic slip at the crack tip. The crack propagation behavior is obviously orientation dependent. Orientation I and orientation II expand in the form of ductile fracture. Orientation III shows obvious brittleness and expands in the form of cleavage fracture. Orientation IV (Orientation I-IV represent the four angles between the crack plane and the crystal orientation) shows both ductile fracture and brittle cleavage fracture. The defects and stress concentration at the crack tip provide a driving force for martensitic nucleation, and the hcp phase produced by martensitic transformation effectively increases the toughness of the crack. The simulation results of molecular dynamics are basically consistent with the theoretical prediction of linear elastic fracture mechanics. This suggests that the variation of the orientation could tune the crack tip plasticity and toughening in B2 phase matrix. [ABSTRACT FROM AUTHOR]

A multi-scale model of dynamic impact fracture of Ni-based deformed superalloy was proposed based on molecular dynamics and finite element methods, and verified by experiments to reveal the synergistic effect of twin and phase boundaries on dynamic fracture properties and behavior from nanoscale to macroscale. The results show that the synergistic effect of twin and phase boundaries can effectively suppress the unfavorable brittle propagation in the nanoscale owing to the dispersed distribution of strengthening phase-induced reduction of the stress concentration on the twin boundary. The nucleation and emission of perfect dislocations, Shockley dislocations, and Frank dislocations promote ductile propagation, while the pile-up of stair-rod dislocations induced stress concentration leads to brittle propagation. In the macroscale, the synergistic effect of twin and phase boundaries can effectively inhibit the loss of dynamic fracture toughness, and impede crack initiation and crack propagation through the reduction of Mises stress concentration and the decrease of maximum equivalent strain caused by the dispersed Ni 3 Al precipitates. The physical mechanism of the multi-scale crack propagation and fracture, and the influence law of dynamic fracture toughness of Ni-based deformed superalloy, can provide a guide to the failure prediction, protection, and development of aviation turbine blades. [ABSTRACT FROM AUTHOR]

FoxA transcription factors play vital roles in regulating the expression of organ-specific genes. BmSGF1, the sole FoxA family member in Bombyx mori , is required for development of the silk gland. However, the function of BmSGF1 in development of the nervous system in the silkworm remains unknown. Here, we show that the amino acids sequence of BmSGF1 is evolutionarily conserved in its middle region from Trichoplax adhaerens to human and diverged from the homologues in most other species in its N-terminal region. BmSGF1 expresses in the nervous system at the embryonic stage. Knockdown of Bmsgf1 by RNA interference (RNAi) results in abnormal development of axons. Therefore, our results demonstrate that BmSGF1 is an indispensable regulator for neurodevelopment. [ABSTRACT FROM AUTHOR]

The experiments and molecular dynamics simulations were employed to further understand the morphology evolution and failure mechanism of the TA15/Ti 2 AlNb interface. The results show that the asymmetric diffusions, caused by the difference of the diffusion coefficient and crystal structure, have played a significant role in the microstructure and mechanical properties. The diffusivity of Ti elements from TA15 was much better than those Nb and Al from Ti 2 AlNb base alloy owing to its higher diffusion coefficient. The macro joints are brittle fractures near the TA15 base zone, and excessive holding time will reduce the tensile strength and plasticity of the joint while increasing the temperature can enhance the strength and plasticity due to the promotion of diffusion and improvement of the microstructure. However, the nano joints are ductile failures owing to size effects. Time has little effect on the mechanical properties of nano joint, while an increase in temperature could improve the strength and plasticity. The combination of MD simulations and experiments provides new approaches for the study of deformation mechanisms and microstructure evolution. • Element diffusion and distributions were investigated from the nanoscale to the microscale. • The asymmetric diffusion was revealed by the diffusion coefficient and crystal structure. • Two fracture behavior and mechanism of the joint were proposed under the different scale. • The fracture mechanism was determined by atomic diffusion and interface morphology. [ABSTRACT FROM AUTHOR]

Summary: Objectives: MicroRNAs (miRNAs) are endogenous small non-coding RNAs that negatively regular target gene expression by RNA interference. The processing of the pre-miRNA hairpin generates a miRNA duplex, which consists of a miRNA (guide strand) and a miRNA∗ (passenger strand). miR-31 is an oncogenic miRNA and is up-regulated in oral squamous cell carcinoma (OSCC). miR-31∗ shows a high level of conservation across species and, based on this, this study hypothesized that miR-31∗ is a functional miRNA. Materials and Methods: The expression of miR-31 and miR-31∗ in OSCC tissues and oral cells were analyzed. Functional studies were performed on OSCC cells. Results: miR-31∗ is up-regulated in OSCC tissues, but its expression is less abundant than miR-31. miR-31∗ decreases the proliferation and migration of both SAS and Fadu cells. Furthermore, miR-31∗ targets the 3′UTR of RhoA and is able to down-regulate RhoA expression. Knockdown of RhoA expression is known to decrease the proliferation and migration of OSCC cells. However, up-regulation of both miR-31 and miR-31∗ by delivery of pre-mir-31 does still enhance OSCC oncogenicity. Conclusion: miR-31∗ is a functional miRNA involving in regulating RhoA, and the activity of miR-31∗ ’s activity seems to counteract the functions of miR-31 during OSCC tumorigenesis. [ABSTRACT FROM AUTHOR]

The molecular dynamics (MD) simulation is performed to obtain the mechanical properties and plastic deformation mechanism of bicrystal structural tungsten (BS W) with equilibrium grain boundaries (EGBs) and non-equilibrium grain boundaries (NEGBs) under tension at different strain rates. The BS W with NEGBs has shown excellent comprehensive mechanical properties, and its yield strength is only about 1.5 Gpa (~10%) lower than that of the BS W with EGBs. The yield strain of BS W with NEGBS is about double than that with EGBs. The micro-deformation mechanisms for BS W with NEGBs under tension are dislocation emission and movement, GBs interaction, and phase transition. However, the failure modes of BS W with EGBs are intergranular brittle fracture of crack near the GBs, and the strain rate has little effect on the fracture. The phase transition mechanism for BS W with NEGBs under the tension loading strain rate of 0.0001 ps−1 is atomic slippage, but that of 0.001 ps−1 is stress concentration induced quasi-reconstructive phase transition. At the loading strain rate of 0.0001 ps−1, dislocation emission and movement to the GBs would form the non-slippable crack dislocations for crack initiation. However, at the loading strain rate of 0.001 ps−1, the crack propagation is considered as a zigzag-shaped form on account that the phase transition induced stress relaxation. The NEGBs could improve plasticity without sacrificing strength, providing a theoretical method for nano-structure design, material modification, and sustainable material plain. Unlabelled Image • Comparing with the NC W with EGBs, that with NEGBs could significantly improve plasticity with a small sacrificing strength. • The strain rate has little influence on the mechanical properties and deformation mechanism of NC W with EGBs. • Two-phase transition mechanisms, atomic-slip, and stress concentration induced. • Two different fracture mechanisms, intergranular fracture, and crack propagation. [ABSTRACT FROM AUTHOR]

The effect of temperatures (1173–1233 K) on the diffusion welding process of the body-centered cubic titanium and the orthorhombic Ti 2 AlNb interface (B 2 –O interface) is investigated and analyzed using molecular dynamics. The result shows that Nb and Al atoms are the primary diffusive atoms in the orthorhombic single-crystal Ti 2 AlNb (O phase), and the diffusive distances of Ti atoms in the Β 2 phase are significantly higher than that of Nb and Al atoms in the O phase. The atomic diffusion within the O phase is downhill diffusion, aggregation and interface formation controlled by Nb and Al atoms. As the temperature increases from 1173 to 1233 K, the average diffusion distances during 900 ps of Nb and Al atoms in the O phase are increased from 1.4 nm to 1.9 nm, while those of Ti atoms during 900 ps in the B 2 phase are increased from 2.8 nm to 3.3 nm. The modified Arrhenius model considering the pressure effect is established to accurately solve the diffusion activation energy. The significant higher diffusion activation energy, and lower diffusion coefficient and diffusion prefactor of the orthorhombic single-crystal Ti 2 AlNb result in shorter atomic diffusive distances in the O phase than that of the B 2 phase. Image 1 • The asymmetric atomic diffusion in the B 2 –O interface is investigated at the atomic scale via molecular dynamics. • The atomic diffusivities are determined by the average atomic diffusion coefficient and activation energy. • Temperature-induced concentration variations play an important role in diffusion thickness and mechanism. • The modified Arrhenius relationship is derived to accurately solve the diffusion activation energy. [ABSTRACT FROM AUTHOR]