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The basic leucine zipper (bZIP) transcription factor family plays an important role in various biological processes in plants. Andrographis paniculata (Burm.f) Nees, belonging to the family Acanthaceae, has been widely used as an important traditional herb with a wide range of pharmacological activities, such as antivenom, antiretroviral, anticancer and so on. However, there was no comprehensive analysis of bZIP gene family in the Andrographis paniculata been reported. In this study, we identified 62 bZIPs in Andrographis paniculata and grouped them into 12 subfamilies through the phylogenetic tree analysis. The bZIPs in the same groups have similar motif composition, exon-intron structure and domain distribution. In addition, the RNA-seq data gave a reference for selecting candidate bZIPs to make further function verification. Lastly, qRT-PCR analyses revealed seven ApbZIPs (ApbZIP4, ApbZIP19, ApbZIP30, ApbZIP42, ApbZIP50, ApbZIP52, ApbZIP62) were the most highly expressed in leaf and significantly up-regulated with MeJA and ABA treatment which may be involved in biosynthesis regulation of andrographolide. These data pave the way for further revealing the function of the bZIPs in Andrographis paniculata. [ABSTRACT FROM AUTHOR]

The influence of atmospheric turbulence inflow on coupled dynamic behaviors and wakes of floating offshore wind turbine (FOWT) is pronounced, especially as blade size increases. In this study, we explore the effects of atmospheric inflow on aero-hydrodynamics and wake characteristics of a spar-type FOWT. A well-validated in-house computational fluid dynamic (CFD) solver, FOWT-UALM-SJTU, is utilized to conduct the numerical simulations. To generate the realistic atmospheric inflow condition, the large eddy simulation (LES) with long-duration is employed. Two other cases involving uniform inflow and shear inflow are conducted to provide some comparable results. Compared to uniform inflow and shear inflow, the power and thrust of FOWT under atmospheric inflow display greater instability, with their power spectrums exhibiting higher intensity in high frequency region. The variation of yaw moment in atmospheric scenario is significantly drastic, leading to a remarkable response in platform yaw motion. Notably, the dominant frequency in this scenario is the blade passage frequency, as opposed to the incident wave frequency observed in the uniform and shear scenarios. The atmospheric inflow promotes the manifestation of wake breakdown and wake meandering, resulting in the faster wake recovery of FOWT. Besides, the meandering in the far wake is more significant compared to uniform and shear scenarios. The absence of vortex rings in atmospheric scenario is observed, along with the presence of more complex and smaller vortices in far wake. Our findings highlight the remarkable impacts of atmospheric inflow on dynamic responses and wake evolution of FOWT, and it is recommended that the atmospheric inflow be taken into account when assessing wake interactions between multiple FOWTs. • The LES is used to generate the physically realistic atmospheric turbulence inflow. • The fully coupled aero-hydrodynamics of FOWT are considered. • Wake characteristics of FOWT are investigated, extending as far as 9D downstream. [ABSTRACT FROM AUTHOR]

The mechanisms associated with the interaction of {332} twins are investigated in metastable Ti 15Mo alloy. There are 12 possible twin-twin junctions (TTJs) induced by {332} twins that can be classified into 5 types according to the crystallographic relation. Twin-twin interactions are accompanied with the formation of twin-twin boundaries (TTBs) on the acute side and obtuse side. Experimental results based on transmission electron microscopy (TEM) and procession electron diffraction (PED) show that subsequent growth of the TTBs is asymmetric with the twin thickening preferred only on one side for each type. Besides, it is observed that the twin-twin interaction could stimulate sequential {332} twinning inside the primary twin with a specific twin variant promoted. To account for the subsequent growth of the TTBs and the preferred selection of the sequential twinning variant associated with twin-twin interactions, the elastic energy analysis of the resultant dislocations at TTBs indicates that the growth of the TTBs is energetically favorable only on one side. Displacement gradient based analysis shows that the active sequential twin variant could maximumly accommodate the accumulated strain induced by the twin-twin interaction. This work is useful for predicting the preferential growth of the interfaces and the associated accommodation mechanisms induced by the interactions of localized shear bands. [Display omitted] • The growth of the interacted {332} twins is preferred only on one side for each type. • Twin-twin interactions could stimulate sequential twinning with a specific variant promoted. • The general analysis method for interaction mechanisms of localized shear bands is proposed. [ABSTRACT FROM AUTHOR]

〈 a 〉dislocations on basal or prismatic planes and { 11 2 ¯ 2 } compression twins are commonly activated in deformed Titanium (Ti). In the present work, their interactions are investigated by both crystallographic analysis and atomistic simulations. For a three-dimensional { 11 2 ¯ 2 } twin, we firstly analyze seven possible twin boundaries (TBs) bonding two low index planes in matrix and twin. Next, we focus on the two lower energy boundaries, { 11 2 ¯ 2 } M / T ∥ { 11 2 ¯ 2 } T / M coherent twin boundary (CTB) and { 1 ¯ 2 1 ¯ 1 } M / T ∥ { 1 2 ¯ 1 1 ¯ } T / M . Depending on dislocation character and boundary type, we define four types of interactions between 〈 a 〉 dislocations and these TBs. Further, we predict possible dislocation reactions on/across TBs using crystallographic analysis according to the deformation compatibility and the change in elastic energy, such as twinning/detwinning of the primary twin, slip transmission and secondary twinning, for each type of interaction. Molecular dynamics (MD) simulations are then conducted for all interactions under pre-selected loadings in order to explore the dynamic process associated with each of these interactions and examine the predicted reactions. MD simulations predict that the interaction between 〈 a 〉 dislocations and some facets can lead to the formation of secondary twins and 〈 a 〉 dislocations on basal or prismatic planes in twins, and reveal the possibility of forming 〈 c 〉 and 〈 c + a 〉 dislocations in twins. Moreover, some of the possible reactions take place on lateral TBs other than CTBs. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Ti and its alloys have a variety of applications in aerospace industry and medical implants. The formation of hydride has been used in biomedical areas and can significantly influence the mechanical performance of materials. In this work, we investigate the orientation dependence of hydride precipitation in commercially pure titanium via interrupted in-situ electron backscatter diffraction (EBSD) measurements. The results reveal that hydrides during hydrogen charging at room temperature exhibit two types of orientation relationships with α-titanium, i.e., { 0001 } α / / { 1 1 ¯ 1 } δ < 1 2 ¯ 10 > α / / < 110 > δ with interface plane { 10 1 ¯ 3 } α / / { 1 1 ¯ 0 } δ (B-type), and {0001} α //{001} δ < 1 2 ¯ 10 > α / / < 110 > δ with interface plane { 10 1 ¯ 0 } α / / { 1 1 ¯ 0 } δ (P-type). Significant orientation dependence of hydride precipitation is observed, especially when { 10 1 ¯ 3 } , { 10 1 ¯ 0 } , {0001} or { 11 2 ¯ 0 } planes of the parent grains are parallel to the diffusion surface. The displacement gradient tensor based accommodation shows that the orientation dependence is attributed to the strain relaxation of hydride transition. Three types of hydride platelets are characterized: parallel hydride platelets (Type I), crossed hydride platelets (Type II) and clustered hydride platelets (Type III). The multiple morphologies of hydride platelets resulting from the hydride variant selection and interaction are dependent on the crystal orientation of the matrix. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The flow near the duct is very important for the efficiency and stable operation of a pump-jet propulsion. To study the flow near the outer surface and outlet of a duct, the larger-eddy simulation (LES) method is used to analyze the flow characteristics under different operating conditions. C v on different lines in the swirling-jet flow obtained by the LES method fits well with that of the laser Doppler velocimeter experiment. Based on the reliable results of numerical simulation, it was found that lower inflow velocity delays the generation of separation vortex on the duct's outer surface. When the developing separation vortex interacts with the swirling-jet flow, the strong interaction may destroy the structure of the tip leakage vortex and has a huge influence on the swirling-jet flow with the increasing advance coefficient. As a result, the stronger interaction makes the downstream swirling-jet flow even more complicated. In addition, the strongest intensity of the hub vortex occurs when the advance coefficient is 1.4. u i ′ u j ′ ‾ is very important for the reallocation of the time-average fluctuation kinetic energy. Therefore, it is selected for further flow analysis. Compared with others terms, u z ′ u z ′ ‾ has larger magnitude and is consistent with the distribution of C k. • The developing flow near the duct of an axial water-jet pump is studied based on LES method under three typical conditions. • With the increasing velocity of inflow, the stronger interaction of separation vortex and swirling-jet flow makes the swirling-jet flow more complicated and uneven. • Compared with others terms, u z ′ u z ′ ‾ has a dominant role for the swirling-jet flow. [ABSTRACT FROM AUTHOR]

Abstract Shock loading causes complicated twinning processes in Ti and Ti alloys. In this work, two types of {10 1 ¯ 2} sequential twinning processes are for the first time reported according to electron backscatter diffraction (EBSD) characterization of titanium sheets that are subjected to shock loading. One is described as {11 2 ¯ 1} ⇒ P → {10 1 ¯ 2} ( T i I I ⇒ P → T j I ), i.e., {10 1 ¯ 2} sequential twinning is activated in the parent grain (P) along with {11 2 ¯ 1} twins. The other is described as {11 2 ¯ 2} ⇒ {11 2 ¯ 4} → {10 1 ¯ 2} ( C i I ⇒ C j I I → T k I ), i.e., {10 1 ¯ 2} secondary twinning is stimulated inside {11 2 ¯ 4} twin by co-zone {11 2 ¯ 2} twin. A statistical analysis according to EBSD characterization reveals the well-defined crystallographic relations between sequential {10 1 ¯ 2} twin variants and the primary/incoming twins, i.e., T i I I ⇒ P → T i I o r T i + 1 I and C i I ⇒ C i + 3 I I → T i I or T i + 1 I . We proposed and examined two sequential twinning mechanisms, (i) emissary twinning disconnections at steps along twin boundary for the first case and (ii) shear transformation into the primary twin for the second case, based on dislocation theory and the deformation accommodation ability of the sequential {10 1 ¯ 2} twinning to the shear deformation of the primary/incoming twin. Crystal plasticity modelling is performed to calculate the local stress field associated with the proposed twinning mechanisms. The results demonstrate that the preferred twin variant observed in experiments has the maximum resolved shear stress among the six twin variants. Our work suggests that complicated twinning processes under shock loading obey crystallographic relations according to deformation accommodation ability. The findings from this study can be implemented into meso-/macro-scale crystal plasticity models for predicting mechanical behaviors and texture evolution of polycrystalline aggregates of hexagonal materials. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract { 11 2 ¯ 2 } twinning commonly takes place in α-titanium (α-Ti). High-resolution transmission electron microscopies (HRTEM) explored various steps along { 11 2 ¯ 2 } coherent twin boundary. Topological model of { 11 2 ¯ 2 } twin revealed twinning disconnections (TDs) that are represented by ( b i , i h { 11 2 ¯ 2 } ) corresponding to a step height i h { 11 2 ¯ 2 } and a shear vector b i. Atomistic simulations were conducted to study the energies and kinetics of TDs. Combining microscopies and atomistic simulations, we concluded that ( b 3 , 3 h { 11 2 ¯ 2 } ) is the elementary TD and ( b 1 , h { 11 2 ¯ 2 } ) is the reassembly TD. Steps observed in HRTEM thus can be treated as a reassembly of ( b 3 , 3 h { 11 2 ¯ 2 } ) TDs and ( b 1 , h { 11 2 ¯ 2 } ) TDs. In addition, Electron Backscatter Diffraction (EBSD) maps revealed { 11 2 ¯ 2 } → { 11 2 ¯ 1 } double twins in α-Ti. Using two-dimensional and three-dimensional atomistic simulations, we demonstrated the nucleation of ( b 1 , h { 11 2 ¯ 2 } ) TD and { 11 2 ¯ 2 } → { 11 2 ¯ 1 } double twin through the interaction between basal < a > dislocation and { 11 2 ¯ 2 } twin. Our results enrich the understanding of { 11 2 ¯ 2 } twinning including TDs, steps, and { 11 2 ¯ 1 } secondary twins in hexagonal metals. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]