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The utilization of stabilized DELLA proteins Rht-B1b and Rht-D1b was crucial for increasing wheat (Triticum aestivum) productivity during the Green Revolution. However, the underlying mechanisms remain to be clarified. Here, we cloned a gain-of-function allele of the GSK3/SHAGGY-like kinase-encoding gene GSK3 by characterizing a dwarf wheat mutant. Furthermore, we determined that GSK3 interacts with and phosphorylates the Green Revolution protein Rht-B1b to promote it to reduce plant height in wheat. Specifically, phosphorylation by GSK3 may enhance the activity and stability of Rht-B1b, allowing it to inhibit the activities of its target transcription factors. Taken together, we reveal a positive regulatory mechanism for the Green Revolution protein Rht-B1b by GSK3, which might have contributed to the Green Revolution in wheat.

This paper reports tensile and compressive test results of bolted glubam (glued laminated bamboo) connections. The tensile tests were carried out with two types of specimens designed for tensile loadings in the longitudinal and transverse directions in relevance to the orientations of the bidirectional bamboo strips (fibers). In each direction, the specimens were further divided into nine groups according to different combination conditions of end and edge spacings. Compressive tests were executed for three groups of bolted glubam connections, with varying thickness of the main board and bolting conditions. The tensile experiments show that the failure of the specimens is strongly influenced by the loading directions. Recommended end distance and side distance are provided, whereas the load carrying capacity is analyzed. Based on the compressive testing results, failure modes and load displacement relationships are analyzed, in which the yield bearing capacity is shown to be close to that given by the equations in existing design specifications for timber structure.

CONSTANS (CO) is a central regulator of floral initiation in response to photoperiod. In this study, we show that the GSK3 kinase BIN2 physically interacts with CO and the gain-of-function mutant bin2-1 displays late flowering phenotype through down-regulation of FT transcription. Genetic analyses show that BIN2 genetically acts upstream of CO in regulating flowering time. Further, we illustrate that BIN2 phosphorylates the Thr280 residue of CO. Importantly, the BIN2 phosphorylation of Thr280 residue restricts the function of CO in promoting flowering. Moreover, we reveal that the N-terminal part of CO harboring the B-Box domain mediates the interaction of both CO-CO and BIN2-CO. We find that BIN2 inhibits the formation of CO dimer/oligomer. Taken together, this study reveals that BIN2 regulates flowering time through phosphorylating the Thr280 of CO and inhibiting the CO-CO interaction in Arabidopsis.HighlightBIN2 regulates flowering time through phosphorylating the Thr280 of CO in Arabidopsis.

Plant adaptation to adverse environment depends on transmitting the external stress signals into internal signaling pathways, and thus forming a variety of stress response mechanisms during evolution. Brassinosteroids (BRs) is a steroid hormone and widely involved in plant growth, development and stress response. BR is perceived by cell surface receptors, including the receptor brassinosteroid-insensitive 1 (BRI1) and the co-receptor BRI1-associated-kinase 1 (BAK1), which in turn trigger a signaling cascade that leads to the inhibition of BIN2 and activation of BES1/BZR1 transcription factors. BES1/BZR1 can directly regulate the expression of thousands of downstream responsive genes. Studies in the model plant

The use of steel has grown rapidly over the past decades. However, corrosion under coating detection still presents challenges for nondestructive testing (NDT) techniques. One of such challenges is the lift-off introduced by complex structures. Inaccessibility due to structure leads corrosion to be undetected, which can lead to catastrophic failure. Furthermore, lift-off effects reduce the sensitivities. The limitations of existing NDT techniques heighten the need for novel approaches to the characterization of corrosion. This paper begins with a discussion of the challenges associated with corrosion detection of metal under coating. Secondly, reviews are given of the most NDT methods used for the detection of corrosion under coating. The different techniques based on nondestructive testing methods such as ultrasonic, acoustic, electromagnetic, radiographic, and thermographic have been detailed out. This review presents the significance and advantages provided by the emerging NDT techniques. In the end, the trends and identified problems are summarized.

Early marine corrosion especially under coating is difficult to be detected, sized and predicted. This work proposed through coating imaging (TCI) based on high frequency electromagnetic induction, thermal wave propagation and infrared temperature field measurement. The proposed method is called electromagnetic induction pulsed phase thermography (EMIPPT), whose advantages include being nondestructive, non-contact, fast speed, large-area, high resolution and visualization. By phase analysis, the complex influence of parameter variation on temperature can be eliminated and then relative variation of corrosion height can be characterized. The mild steel (S275) samples providing coated real marine atmosphere corrosion with exposure from 1, 3 and 6 months were tested. The experimental results illustrate that EMIPPT has greater potential for in-service corrosion detection, sizing and monitoring than laser profilometry, pulsed eddy current, and microwave waveguide.

Cancer is a complex disease involving multiple genomic alterations that disrupt the dynamic response of signaling networks. The heterogeneous nature of cancer, which results in highly variable drug response, is a major obstacle to developing effective cancer therapy. Previous studies of cancer therapeutic response mostly focus on static analysis of genome-wide alterations, thus they are unable to unravel the dynamic, network-specific origin of variation. Here we present a network dynamics-based approach to integrate cancer genomics with dynamics of biological network for drug response prediction and design of drug combination. We select the p53 network as an example and analyze its cancer-specific state transition dynamics under distinct anticancer drug treatments by attractor landscape analysis. Our results not only enable stratification of cancer into distinct drug response groups, but also reveal network-specific drug targets that maximize p53 network-mediated cell death, providing a basis to design combinatorial therapeutic strategies for distinct cancer genomic subtypes., Genomic alterations underlie the variability of drug responses between cancers, but our mechanistic understanding is limited. Here the authors use the p53 network to study how rewiring of signalling networks by genomic alterations impact their dynamic response to pharmacological perturbation.

Solar energy is one of the fastest growing renewable energy resources. It is extremely important to improve the reliability and availability of solar energy systems and to further reduce the operation and maintenance (O&M) cost. Solar cells and modules are considered as one of the most critical components in solar energy system because they convert solar energy into electricity. Flaws and damages are inevitable during either the fabrication or the service life of a solar cell or module. Thus, nondestructive inspection, testing and evaluation (NDI, NDT& NDE) for solar cells and modules are required in both manufacturing quality control and in-service inspection. In this work, a fully, in-depth and comprehensive review of NDT&E techniques for Si-based, thin film and multi-junction solar is reported based on an orderly and concise literature survey. Firstly, the developments and case comparison studies of electromagnetic, sonic and ultrasonic, optical, thermal, near-infrared, terahertz and mechanical test NDT&E for Si-based solar cells especially in the last three years are reviewed in detail. Next, the developments of NDT&E methods for film and multi-junction solar cells are also reviewed. After that, the strengths and limitations of these NDI and NDT techniques are concluded through comparison studies. Analytic hierarchy process (AHP) is used to compare 7 kinds of NDT methods which include photoluminescence (PL), electroluminescence (EL), illuminated lock-in thermography (ILIT), dark lock-in thermography (DLIT), resonance ultrasonic vibration (RUV), optical NDT and lamb wave air coupled ultrasonic testing (LAV-UT). In addition, the development tendencies for solar cell and related NDT&E are predicted. This work will serve as a guide for performance testing, failure analysis, quality control and health monitoring of Si-based cells, thin film and multi-junction solar cells and play an important role in solar energy safety control and cost saving.

Glued-laminated bamboo (glubam) is a new type of structural material, which is developed as a potential alternative to the glued-laminated lumber or glulam. Similar to modern timber structures, connecting the glubam elements using steel joints requires a good understanding of the shear behavior of the material. In this study, glubam boards with three different bamboo strip (or fiber) configurations are manufactured and studied. Three types of glubam boards were manufactured and tested, including glubam with two bidirectional fiber arrangements at the ratios of 4:1 and 1:1, respectively, in the two orthogonal directions, and also the unidirectional fiber arrangement. The shear strengths in different loading conditions are experimentally investigated, following testing specifications for conventional wood. The study found that the in-plane shear strength values follow a normal distribution well, whereas the out-of-plane shear strength values can be statistically expressed by Weibull distribution. Based on the test results, the out-of-plane shear strengths and the in-plane shear strengths of glubam are studied, and the characteristic values and the design values are suggested. The relationship between the out-of-plane shear strength and the bidirectional ratio of bamboo strip (or fiber) has also been obtained with reasonably good correlation to the test results.

Conventional active thermography heats the surface of materials by using conductive thermal sources like hot water, convective thermal sources like air jet, or irradiative thermal sources like a flash lamp. Quantification and characterization methods are mainly built on heat conduction from surface to inner. Currently, electromagnetic induction, microwave and terahertz wave are increasingly used for heating advanced materials such as composites, polymers and biomaterials. Their heating principles and quantification methods vary widely from that of conventional surface heating thermography. This work presented volume heating thermography (VHT) and inside heating thermography (IHT) for advanced composite materials through these electromagnetic excitations. Physical principle of VHT/IHT for defect quantification has been investigated, and several specific VHT/IHT methods have been built in style of (square) pulse and step analysis in time domain and phase analysis in frequency domain, such as volume lock-in thermography. 1D solution, simulation involving 3D finite element model and experiments studies demonstrate that polytetrafluoroethylene insert, impact, and delamination in carbon fibre reinforced polymer can be qualitatively detected and characterised using proposed methods, especially in phasegram after eliminating non-uniform heating effect and periodic structures. VHT and IHT through electromagnetic induction, microwave and terahertz wave have a potential application on inspection and characterization of composites, polymers and biomaterials.

High frequency RFID sensors are attractive in diverse applications where sensor performance is required at a low cost and dimension restriction. An approach adapting commercial passive 13.56 MHz RFID tags has been developed for sensing corrosion stage. This investigation includes balance of sensing and positioning of RFID sensors for corrosion detection by analysing real and imaginary parts of the complex impedance. With passive HF RFID sensors, real part and imaginary part of complex impedance have been extracted from the reader coil with VNA (vector network analyser) and delivering a unique capability for corrosion sensing with different atmospheric exposure time steel samples (1 month, 6 months, 10 months and 12 months). With different positioning (5–25 mm), features extraction based on the complex impedance with PCA (principal component analysis) has been designed for position-independent corrosion evaluation.

Wind energy is one of the fastest growing renewable energy resources. It is distinctly important to increase reliability and availability of wind turbines and further to reduce the wind energy cost. Blades are considered to be one of the most critical components in wind turbine system because they convert Kinetic energy of wind into useable power. Blades are fabricated by carbon fiber reinforced polymer (CFRP) or glass fiber reinforced polymer (GFRP). Flaws and damages are inevitable during either fabrication or lifetime of a composite blade. Thus, non-destructive testing (NDT) and structural health monitoring (SHM) for wind turbine blade (WTB) are required to prevent failures and increase reliability in both manufacturing quality control and in-service inspection. In this work, a fully, in-depth and comprehensive review of NDT techniques for WTB inspection was reported based on an orderly and concise literature survey. Firstly, typical flaw and damage occurring in manufacturing progress and in service of WTB were introduced. Next, the developments of visual, sonic and ultrasonic, optical, electromagnetic, thermal and radiographic NDT for composite WTB inspection were reviewed. Thereafter, strengths and limitations of NDT techniques were concluded through comparison studies. In the end, some research trends in WTB NDT have been predicted, for example in combination with SHM. This work will provide a guide for NDT and SHM of WTB, which plays an important role in wind turbine safety control and wind energy cost savings. In addition, this work can benefit the NDT development in the field of renewable energy, such as solar energy, and energy conservation field, such as building diagnosis.

Polymer-matrix composites (PMCs) such as glass fibre reinforced polymer (GFRP) and carbon fibre reinforced polymer (CFRP) are being increasingly used in fields of aerospace, renewable energy, civil and architecture. Damages such as broken fibre, impact and delamination are inevitable during either fabrication or lifetime of PMC structures or components. This work proposed selectively heating thermography (SeHT) through electromagnetic induction and infrared temperature measurement for CFRP characterisation and damage inspection. Broken carbon fibres can be easily identified through SeHT whilst inside delamination is difficult to be inspected due to negative influence of temperature gradient, lateral blur effect, and periodic structures. In order to solve this problem, cross correlation (CC) matched filtering algorithm was proposed to enhance the inspection results. Six CFRP laminate samples with impact damages from 2 to 12 J were tested to verify the proposed methods. The experimental studies show that SeHT is capable of characterising fibres and inspecting surface broken area, whilst CC phasegram is capable of inspecting inner delamination due to elimination of non-uniform heating effect and lateral blurring effect. The dependence of damage for CFRP sample on impact energy was also investigated. Through SeHT and CC matched filtering, characterisation and inspection for CFRP can be achieved.

A new chemoresistance mechanism via bimodal p53 activation is attributed to differential output of a four-component control module., Studies of drug resistance mostly characterize genetic mutation, and we know much less about phenotypic mechanisms of drug resistance, especially at a quantitative level. p53 is an important mediator of cellular response to chemotherapy, but even p53 wild-type cells vary in drug sensitivity for unclear reasons. Here, we elucidated a new resistance mechanism to a DNA-damaging chemotherapeutic through bimodal modulation of p53 activation dynamics. By combining single-cell imaging with computational modeling, we characterized a four-component regulatory module, which generates bimodal p53 dynamics through coupled feed-forward and feedback, and found that the inhibitory strength between ATM and Mdm2 determined the differential modular output between drug-sensitive and drug-resistant cancer cell lines. We further showed that the combinatorial inhibition of Mdm2 and Wip1 was an effective strategy to alter p53 dynamics in resistant cancer cells and sensitize their apoptotic response. Our results point to p53 pulsing as a potentially druggable mechanism that mediates chemoresistance.

Composites, such as glass fiber reinforced polymer (GFRP) and carbon fiber reinforced polymer (CFRP), and adhesive bonding are being increasingly used in fields of aerospace, renewable energy, civil and architecture, and other industries. Flaws and damages are inevitable during either fabrication or lifetime of composites structures or components. Thus, nondestructive testing (NDT) are extremely required to prevent failures and to increase reliability of composite structures or components in both manufacture and in-service inspection. Infrared thermography techniques including pulsed thermography, pulsed phase thermography, and lock-in thermography have shown the great potential and advantages. Besides conventional optical thermography, other sources such as laser, eddy current, microwave, and ultrasound excited thermography are drawing increasingly attentions for composites. In this work, a fully, in-depth and comprehensive review of thermography NDT techniques for composites inspection was conducted based on an orderly and concise literature survey and detailed analysis. Firstly, basic concepts for thermography NDT were defined and introduced, such as volume heating thermography. Next, the developments of conventional optic, laser, eddy current, microwave, and ultrasound thermography for composite inspection were reviewed. Then, some case studies for scanning thermography were also reviewed. After that, the strengths and limitations of thermography techniques were concluded through comparison studies. At last, some research trends were predicted. This work containing critical overview, detailed comparison and extensive list of references will disseminates knowledge between users, manufacturers, designers and researchers involved in composite structures or components inspection by means of thermography NDT techniques.

Major problems in eddy current thermography include the compromise between depth dynamic range and resolution, the influence of surface emissivity variation and the low defect detectability. This paper presents pulsed inductive thermal wave radar (PI-TWR) by introducing the cross correlation (CC) matched-filtering in eddy current pulsed thermography (ECPT). CC phase and CC peak phase delay are used as characteristic features. The proposed method was verified through numerical and experimental studies, where steel sample and carbon fibre reinforced polymer (CFRP) sample were tested under transmission and reflection modes. The results illustrate a significant improvement in the dynamic range, depth resolution, emissivity variation reduction and detectability of subsurface defects and inside delamination for the nondestructive testing applications.

This study presents a microstructural topology optimization-based method for dealing with the problem of minimizing the sound power flow that radiates from a vibrating composite plate. The plate is assumed to be constructed with periodic microstructures that are uniformly distributed over the macrostructural domain. The design variable in this case is the relative material volume density of the unit cell of the microstructure. The equivalent macromaterial properties of the microstructure are calculated using the homogenization method, and the bi-material solid isotropic material with penalization model is employed to achieve a zero-one design at a microscale. The high frequency approximation formulation and the weak coupling assumption are adopted to achieve an efficient overall analysis and sensitivity analysis of the coupling system. The proposed method is validated by several numerical examples. Results show that effective vibroacoustic isolation may be implemented by the topology design of periodical microstructures.

Rail tread oblique crack, initiated by rolling contact fatigue (RCF) damage, is one of the most significant phenomena and has serious influence on rail industry. Electromagnetic non-destructive testing (EM NDT) methods are usually used in rail regular inspection. However, the conventional EM NDT methods based on eddy current field distribution are difficult to detect the cracks parallel to the inductive coil (parallel cracks) and natural oblique cracks. This paper studied lateral heat conduction (LHC) induced by eddy current for detection of these defects. The proposed method was verified through both numerical and experimental studies as well as the investigation of characteristic of LHC. Due to significant temperature gradient in the direction of lateral heat conduction, the spatial derivative and gradient were proposed to improve the defect detectability on the thermograms. Finally, the test of natural oblique cracks on a rail was conducted to validate the proposed methods.

Mechanisms that determine drug sensitivity of distinct cancer types is poorly understood for most cytotoxic chemotherapy. In this study, we elucidated a new resistance mechanism to DNA damaging chemotherapeutic through modulation of p53 dynamics. While both sensitive and resistant cancer cell lines activated similar p53 oscillation followed by cell-cycle arrest in response to low dose of DNA damaging drug, they switched in a bimodal manner to monotonic or single pulse dynamics at high drug dose. Cell lines with monotonically increasing p53 underwent rapid and extensive drug-induced apoptosis, while those exhibiting a single p53 pulse mostly survived. By combining single cell imaging with computational modeling, we characterized a regulatory module involving ATM, p53, Mdm2 and Wip1, which generates bimodal p53 dynamics through coupled feed-forward and feedback, and we found that basal expression of ATM determined the differential modular output between drug sensitive and resistant lines. Moreover, we showed combinatorial inhibition of Mdm2 and Wip1 was an effective strategy to alter p53 dynamics in resistant cancer cells and sensitize their apoptotic response. Our results point to p53 pulsing as a potentially druggable mechanism that mediates resistance to cytotoxic chemotherapy.

The progression characterisation of exposed atmospheric corrosion on metal substrates is a major problem in the field of corrosion science and Non-destructive Evaluation (NDE). High frequency radio frequency identification (HF RFID) sensors are attractive in diverse applications where sensor performance is needed at a low cost and dimension restriction. An approach adapting commercial passive 13.56MHz RFID tags for sensing corrosion stage has been developed. The investigation includes balance of sensing and positioning of RFID sensors for corrosion detection by analysing real part and imaginary part of the complex impedance. With passive RFID sensors, real part and imaginary part of complex impedance are extracted from the reader coil with Vector network analyser (VNA) and delivering a unique capability for corrosion sensing with different atmospheric exposure time steel samples (1 month, 6 months, 10 months and 12 months). The relationship between these features and corrosion exposed time has been derived which is useful for corrosion progression measurement, early stage corrosion monitoring and prediction in industrial fields such as the marine industry.

This paper deals with the problem of parameter optimization of the motion control mechanism of the hatch door of ARJ21-700, a regional airliner of China. Motion improvement of the hatch door is implemented by two kinds of passive designs. Firstly, a single-layer optimization model for trajectory modification is developed to find the optimum size of the key parts of the control mechanism. Secondly, a novel nested bi-level optimization model is presented for the design of the size tolerance limits of the selected parts. The design objective is minimization of the total extremum deviation of the motion trajectory of the objective point of the hatch door, where the extremum deviation is obtained by solution of the inner-level size optimization problem for the fixed size tolerance limits. The optimization models for motion control of the hatch door mechanism are solved using the response surface method. Numerical examples show that the precision of the real running trajectory of the objective point of the hatch door mechanism may be improved effectively by using the methods presented. A home-made multi-body dynamics solver (THUSOLVER) and the corresponding optimization software have been developed to implement the above tasks.

Longitudinal heat conduction from surface to inside of solid material could be used to evaluate the subsurface defects. Considering that the skin depth of high frequency eddy current in metal is quite small, this paper proposed logarithmic analysis of eddy current thermography (ECT) to quantify the depth of subsurface defects. The proposed method was verified through numerical and experimental studies. In numerical study, ferromagnetic material and non-ferromagnetic material were both considered. Results showed that the temperature–time curve in the logarithm domain could be used to detect subsurface defects. Separation time was defined as the characteristic feature to measure the defect’s depth based on their linear relationships. The thermograms reconstructed by logarithm of temperature can improve defect detectability.

A novel design method based on layout evolution of the periodic micro unit cell of the metamaterial is presented for improvement of the mechanical behavior of the composite structure. The macro properties of the metamaterial depend strongly on its microscopic layout, and hereby may possibly be improved by microstructural design. Topology optimization model and the solution method based on inverse homogenization process are developed to find the best layout of the microstructure. The proposed method may be applied to improve the static and vibro-acoustic behavior of the structure, which is validated by several numerical examples.

Glubam is a new construction material using laminated bamboo with bidirectional fibers. In this paper, we present the failure analysis of glubam with bidirectional fibers using Hankinson formula and Tsai–Wu failure criterion. Off-axis tension tests were performed on glubam specimens with longitudinal to transverse fiber ratio of 4:1. The glubam specimens were designed to study its tensile properties in different directions to the main fiber. A revised Hankinson equation suitable for glubam are developed yielding satisfactory agreement with the test results. It is found that the interaction coefficient F12 in Tsai–Wu failure theory can only be established from the 15° off-axis tension test. Also, three approximation methods, Tsai–Hill, “Hoffman”, and “Mises–Hencky” methods, are applied to estimate the value of interaction F12. Four failure envelopes of glubam have been presented and compared. By comparing with off-axis test data, the failure envelope from Tsai–Wu theory provides unconservative prediction when in-plane shear is ignored. Even when in-plane shear is considered, the failure envelope obtained from Tsai–Wu theory is still deemed unsuitable to represent the behavior of glubam. Therefore, it seems the empirical approach is currently appropriate to represent the behavior of the 4:1 glubam subjected to biaxial tensile stress state.

Bamboo is well-known because of its characteristics of being fast-growing, eco-friendly and of high strength/weight ratio. In today’s trend of sustainable development, there is a renewed interest to use bamboo for modern building and bridge structures. However, traditional use of raw bamboo culms is not the only and the most effective application in construction. Studies on glue laminated forms of bamboo have emerged around the world. The authors developed a laminated bamboo or glubam for general structural applications. This paper introduces the manufacturing process of glubam, investigates and analyzes its energy consumption and carbon dioxide emission, and provides main mechanical properties through material testing. Analysis results and comparison with other comparable construction materials show the eco-friendly performance of glubam. The mechanical properties of glubam are found using methods developed for timber material. The results show that glue laminated bamboo or glubam is promising for general use in construction.

Pulsed eddy current (PEC) response is a complex mix of many factors, including conductivity, permeability, lift-off, and material thickness variation, which should all be taken into account in PEC testing. The influences of material properties on PEC responses in the time domain are investigated and normalization technique is used to reduce the lift-off effect. After this, two time-domain features, representing conductivity and permeability (magnetic field intensity) are extracted. These features are utilized to measure stress in an aluminum alloy, to detect defects in a honeycomb sandwich structure, to evaluate low-energy impact defects in CFRP materials, and to characterize atmospheric corrosion on steel samples.

Active infrared (IR) thermography techniques including pulsed thermography, lock-in thermography, pulsed phase thermography, and step thermography have shown great potential. Besides conventional optical thermography, other sources, such as laser, eddy current, microwave, and ultrasound excited thermography, are drawing attention. This chapter mainly includes two sections. In the first section, basic concepts and classifications of active thermography are defined and introduced. The strengths and limitations of several active thermography techniques are concluded through comparison studies. In the second section the principle, history, and classification of eddy current thermography is introduced.