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The synthetic filament winder drives the filament through the traverse mechanism with rotary wings so that it can complete the transverse reciprocating motion when it is continuously wound and achieve the spiral distribution on the cylindrical package. When the existing traverse mechanism leads the filament, the filament is easy to oscillate and breaks away from the control of the rotary blade during the reversing process at both ends of the package, which directly affects its forming on the package. In this study, firstly, the filament leading process is analyzed from the filament leading principle of the traverse mechanism with rotary wings and the key points of the profile are identified. Secondly, we applied parameter constraints of key points and developed a blade profile that can not only meet the demand of filament reversing but also improve the above abnormal phenomena by curve-fitting, so that the blade can continuously and stably lead and control the filament during the reversing process. Finally, through the actual winding experiment, we contrasted the state of the filament leading process of the original blades with the improved blades, and verified the improvement effect. This study provides a design basis and optimization reference for realizing a smooth and stable relay between the filament and blades. [ABSTRACT FROM AUTHOR]

Yarn tension during ring spinning is influenced by the shape of the balloon. With the high speed of ring spinning, the existing balloon control technology will have problems with yarn breakage caused by increased tension and yarn wear during the spinning process. Therefore, this article takes the naturally formed multi-balloon as the research object and analyzes the force of the yarn in the balloon section to establish the mathematical model of the steady-state balloon section. Then we selected the appropriate parameters to compare the balloon trajectory graph obtained by simulation and experiment, to verify the validity of the mathematical model. Finally, the relationship between the yarn tension and the number of balloon segments under different balloon heights and spindle speeds, and the conditions for the stable shape of multi-balloon are discussed. It was found that under different balloon shapes, increasing the number of balloon segments can effectively reduce the yarn tension at the yarn guide, and the stable conditions of balloons with different numbers of segments under certain process conditions. The findings are of great significance to the subsequent research on the technological parameters of low-tension spinning and the structural design of ring-spinning machines. [ABSTRACT FROM AUTHOR]

Shoot branching is a complex and tightly regulated developmental process that is essential for determining plant architecture and crop yields. The outgrowth of tiller buds is a crucial step in shoot branching, and it is influenced by a variety of internal and external cues. This review provides an extensive overview of the genetic, plant hormonal, and environmental factors that regulate shoot branching in several plant species, including rice, Arabidopsis, tomato, and wheat. We especially highlight the central role of TEOSINTE BRANCHED 1 (TB1), a key gene in orchestrating bud outgrowth. In addition, we discuss how the phytohormones cytokinins, strigolactones, and auxin interact to regulate tillering/branching. We also shed light on the involvement of sugar, an integral component of plant development, which can impact bud outgrowth in both trophic and signaling ways. Finally, we emphasize the substantial influence of environmental factors, such as light, temperature, water availability, biotic stresses, and nutrients, on shoot branching. In summary, this review offers a comprehensive evaluation of the multifaced regulatory mechanisms that underpin shoot branching and highlights the adaptable nature of plants to survive and persist in fluctuating environmental conditions. [ABSTRACT FROM AUTHOR]

Hypoxic-ischemic encephalopathy (HIE) at high-altitudes leads to neonatal mortality and long-term neurological complications without effective treatment. Acer truncatum Bunge Seed extract (ASO) is reported to have effect on cognitive improvement, but its molecular mechanisms on HIE are unclear. In this study, ASO administration contributed to reduced neuronal cell edema and improved motor ability in HIE rats at a simulated 4500-meter altitude. Transcriptomics and WGCNA analysis showed genes associated with lipid biosynthesis, redox homeostasis, neuronal growth, and synaptic plasticity regulated in the ASO group. Targeted and untargeted-lipidomics revealed decreased free fatty acids and increased phospholipids with favorable ω-3/ω-6/ω-9 fatty acid ratios, as well as reduced oxidized glycerophospholipids (OxGPs) in the ASO group. Combining multi-omics analysis demonstrated FA to FA-CoA, phospholipids metabolism, and lipid peroxidation were regulated by ASO treatment. Our results illuminated preliminary metabolism mechanism of ASO ingesting in rats, implying ASO administration as potential intervention strategy for HIE under high-altitude. Acer truncatum Bunge Seed extract (ASO) can potentially alleviate brain injuries in neonates affected by hypoxic-ischemic encephalopathy exposed to high-altitude conditions by protecting the nervous system and improving motor and cognitive abilities. [ABSTRACT FROM AUTHOR]

Rich nontrivial topological phases rooted in the interplay between magnetism and topology in the layered antiferromagnet EuCd2As2 have captured vast attention, especially the ideal Weyl semimetal state realized in the spin‐polarized ferromagnetic (FM) structure driven by a moderate external magnetic field. In this work, combining magnetization, magneto‐transport, and structure measurements under high pressure and first principles calculations, this study finds that the pressure can drive the in‐plane antiferromagnetic structure of EuCd2As2 across an intermediate in‐plane FM structure then into the out‐of‐plane FM structure. This study also finds butterfly‐shaped MR and anomalous Hall effect under large pressure, which may support the pressure‐driven FM state. High‐pressure angle‐dispersive X‐ray diffraction and X‐ray absorption near‐edge spectroscopy measurements exclude structure transition and/or change of Eu2+ valence state as sources for the magnetic phase transitions. Alternatively, apparently reduced axial ratio (c/a) and compressed Eu‐layer space distance should play important roles. Interestingly, the calculations unveil that the out‐of‐plane FM structure hosts only one pair of Weyl nodes around the Fermi level, suggesting that pressure can be an alternative way to realize the ideal Weyl semimetal state in EuCd2As2 and will be useful for exploring exotic topological properties in such layered magnetic topological phase with strongly competing magnetic exchanges. [ABSTRACT FROM AUTHOR]

During the winding process, the filament moves at a high speed with multiple configurations and large deformations, and is acted upon by winding tension, contact force, transverse force, air resistance, and so on. Accurately predicting the trajectory and tension fluctuation of the filament under the high-speed running condition is the basis for regulating winding parameters and ensuring high-quality winding. This paper proposed a novel dynamic approach for modeling the polyester filament winding system. The filament element was established by absolute nodal coordinate formulation. The nonlinear spring and viscous damper elements were used to establish the contact model between the filament and the mechanical parts, and the mechanical model of the influence of the airflow on the filament was established. Through considering the moving filament and all the force factors, the dynamic model of the multi-body coupling system of the filament winding and the corresponding nonlinear dynamic equation were established, and the dynamic equations were solved using MATLAB. An example of the high-speed winding system was simulated and further analyzed, and the simulated trajectory of the moving filament was highly consistent with the experimental image record. [ABSTRACT FROM AUTHOR]

The morphology-dependent behavior of nanomaterials under high pressure has always been a research hotspot due to its great importance in the materials science and physical science fields. Here, we performed in situ high-pressure X-ray absorption fine structure (XAFS) measurements on wurtzite ZnS nanorods and nanoparticles. The XAFS signals show that wurtzite ZnS nanorods transform to the rock salt phase around 19–20 GPa without undergoing the transition to a zinc blende structure, consistent with the high-pressure XRD results. The fitting of the Zn–S bond length in the first shell manifests that the atoms in the ZnS nanorods are more challenging to compress than those in nanoparticles, and the nanorod-type wurtzite ZnS undergoes an abrupt lattice change when directly transitioning to the rock salt structure. The results reveal that the nanorod morphology presents high stability for wurtzite ZnS due to the low-energy circumferential surface of ±(21¯0). Our findings suggest that the nanorod is an ideal morphology for wurtzite ZnS in practical applications and will contribute to investigating the morphology effects on nanomaterials. [ABSTRACT FROM AUTHOR]

A filament bundle is a type of yarn, which is composed of nearly parallel and highly oriented polymer monofilaments. Due to its nonlinearity both in material constitutive properties and structure, the filament bundle possesses nonlinear viscoelastic properties. It is important to study the dynamic behavior of the filament bundle accurately during its high-speed movement. Therefore, an accurate expression of the constitutive relation of the filament bundle is an essential prerequisite for its dynamic simulation and analysis. Continued the previous study in Part I: modeling filament bundle method, in this paper, an approach was proposed to identify the equivalent dynamic constitutive parameters of the filament bundle considering frequency-dependent characteristics. Firstly, the identification formulas of the dynamic elastic modulus and viscoelastic coefficients were derived based on the Kelvin model. Then, a testing method of the cross-sectional parameters of the filament bundle under a certain tension was proposed, and the testing device was developed to obtain the area of the filament bundle; The dynamic loading test of the bundle filament was conducted in a DMA Q800 dynamic mechanical tester. Thirdly, the equivalent dynamic elastic modulus and viscoelastic coefficients were obtained through the experimental test. Finally, an analytical method was proposed to verify the correctness of experimental results through simulation. The results show that the excitation frequency has a significant influence on the dynamic elastic modulus and viscoelastic coefficient, and the curves of the equivalent dynamic elastic modulus and viscoelastic coefficient present nonlinear variation characteristics. [ABSTRACT FROM AUTHOR]

N-terminal acetylation is one of the most common protein modifications in eukaryotes, and approximately 40% of human and plant proteomes are acetylated by ribosome-associated N-terminal acetyltransferase A (NatA) in a co-translational manner. However, the in vivo regulatory mechanism of NatA and the global impact of NatA-mediated N-terminal acetylation on protein fate remain unclear. Here, we identify Huntingtin Yeast partner K (HYPK), an evolutionarily conserved chaperone-like protein, as a positive regulator of NatA activity in rice. We found that loss of OsHYPK function leads to developmental defects in rice plant architecture but increased resistance to abiotic stresses, attributable to perturbation of the N-terminal acetylome and accelerated global protein turnover. Furthermore, we demonstrated that OsHYPK is also a substrate of NatA and that N-terminal acetylation of OsHYPK promotes its own degradation, probably through the Ac/N-degron pathway, which could be induced by abiotic stresses. Taken together, our findings suggest that the OsHYPK-NatA complex plays a critical role in coordinating plant development and stress responses by dynamically regulating NatA-mediated N-terminal acetylation and global protein turnover, which are essential for maintaining adaptive phenotypic plasticity in rice. N-terminal acetyltransferase A (NatA) acetylates approximately 40% of human and plant proteomes. This study reveals that OsHYPK acts as both a positive regulator and a substrate of NatA to coordinate plant development and stress responses by dynamically regulating NatA-mediated N-terminal acetylation and global protein turnover, thereby promoting adaptive phenotypic plasticity in rice. [ABSTRACT FROM AUTHOR]

The band gap is an important property of a semiconductor, and a candidate material with a highly tunable band gap under external tuning parameters will offer wider applications in optoelectronic devices and photocatalytic fields. Here, we show that the layered semiconductor Zn3In2S6 possesses a band gap that is highly tunable with pressure. In situ optical absorption shows that the band gap unexpectedly widens with pressure up to ∼13 GPa. Sudden gap narrowing then occurs above 14 GPa, which is followed by progressive gap decreases on further compression and the gap finally closes above 20 GPa. Our study, encompassing X-ray diffraction, Raman spectroscopy experiments and theoretical calculations revealed that the selective responses of the different bonds are responsible for the band gap increase in the low-pressure ranges. We show that the pressure-induced irreversible amorphization is responsible for the sudden gap narrowing whereas the semiconductor–metallic transition is related to the amorphous–amorphous transition at high-pressure due to a change in the local coordination number of Zn atoms. This work demonstrates the high tunability of the electronic and optical properties of layered ternary semiconductors under pressure, providing a potential way for wider applications of this class of materials. [ABSTRACT FROM AUTHOR]

An artificial ligament tensile and torsion fatigue testing device was designed aiming at the implant failure of artificial ligaments due to stretching and torsion in vivo. The device was composed of a computer, a fabric strength tester, a mechanical sensor, an upper clamping device and a torsion fatigue device component that simulates the shear load of the anterior cruciate ligament of the human body. Two self-made artificial ligaments with braiding structures were used for tensile and torsion fatigue testing to verify the feasibility of the device. The results indicate that the apparent morphology of the artificial ligament is partially altered after fatigue loading and that fiber dislocation due to the torsional shear loading may cause postoperative complications, in addition to a loss of tensile and elastic recovery properties of the artificial ligament. The device has good simulation and testing stability, which can provide guidance for the research and development, industrialization and clinical use of the artificial ligament. [ABSTRACT FROM AUTHOR]

During the high-speed winding of polyester filament, a contact roller must be applied to press on the filament package's surface to ensure the filament is placed stably and precisely on the package surface. Thus, a twin-rotor system with contact coupling characteristics between the contact roller and the filament package is formed. Identifying the contact parameters between the contact roller and the package are prerequisite to precisely analyze the dynamic behavior of the winding system, as well as to determine the technical parameters. In this paper, an approach was proposed to identify the equivalent contact stiffness and contact damping coefficients by means of coordination through experiment and simulation. First, based on the forced non-resonance method of a single-degree-of-freedom system, the testing scheme was drawn up in consideration of the winding process parameters. Then, an experimental device for the twin-rotor system was developed, and the dynamic contact parameters just in the working frequency band corresponding to low linear speed of winding were obtained by the experiment, due to the requirement of the forced non-resonance theory and economic limitations of the experimental device. Third, the basic parameters including equivalent radial Young's modulus and damping ratio of the package were obtained through experimental test. Furthermore, the contact parameters in the working frequency band corresponding to high linear speed of winding were obtained through simulation. Finally, the curve fitting of contact parameters was finished; in addition, the comparative results between the simulation and the experiment are in good agreement. The dynamic contact parameters present nonlinear frequency variation characteristics. [ABSTRACT FROM AUTHOR]

Featured Application: Flexible support is often used in high-speed flexible rotor systems, such as the textile winding rotor, to make the rotor pass smoothly through the critical speed points. The structural coupling, as well as time-varying and frequency-dependent parameters increase the complexity of the winding rotor dynamic behaviors and the difficulty of vibration control. This paper presents a method to reveal the dynamic behavior of the winding rotor through simulation analysis and non-contact test measurement, which have important potential applications in the design of flexible rotor structural parameters and process parameters. To satisfy the requirements of high speed, large capacity and constant winding, a textile winding rotor needs to work in a wide rotation speed range and frequently pass through critical speed points. Thus, the winding rotor adopts the flexible long shaft coupling structure and flexible support with rubber O-rings. This kind of rotor has a multi-coupling structure and frequency-dependent parameters characteristics, especially representative and universal in the dynamic analysis method of the high-speed rotor. In this paper, an approach was proposed to investigate the dynamic behavior of the winding rotor considering the flexible coupling and frequency-dependent supporting parameters. Firstly, a dynamic model of the winding rotor was established by using a Timoshenko beam element. Its dynamic behaviors were simulated by considering the time-varying rotation speed and the frequency-dependent parameters of flexible support. Secondly, a non-contact measuring device was developed for measuring the vibration displacement of the winding rotor in three different speed-up times. Finally, based on simulation and measurement data, how flexible support parameters and the speed-up time affect the winding rotor passing through the critical speed point of the rotor smoothly is revealed. The methods and findings reported here can be used for theoretical and experimental vibration analysis of other types of high-speed flexible rotors. [ABSTRACT FROM AUTHOR]

Complete emergency measures are one of the important guarantees for effective emergency response. An evaluation method based on User-Generated Content (UGC) data is proposed to assess the completeness of emergency measures. To implement this method, UGC data comprising emergency needs from the users and emergency plans comprising emergency measures for specific emergency were firstly collected using a crawler program. A feature template was then established to identify relationships between different features, and a Conditional Random Field (CRF) model was used to extract emergency measures from the emergency plan and emergency needs from UGC data. The Siamese network was applied thereafter to compute the similarity between the emergency measures and emergency needs. The missing emergency measures were obtained based on the similarities, and a quantitative method to calculate the completeness was defined. Finally, using province A as a case study, the emergency measure completeness was evaluated and the emergency measures that need to be strengthened and improved were identified. [ABSTRACT FROM AUTHOR]

A key factor that determines the mechanical and electrical performance of graphene-based materials and devices is how graphene behaves under extreme conditions, yet the response of few-layer graphene to high shear stress has not been investigated experimentally. Here we applied high pressure and shear to graphene powder using a rotational diamond anvil cell and studied the recovered sample with multiple means of characterization. Sustaining high pressure and shear, graphene breaks into nanometer-long clusters with generation of large number of defects. At a certain stress level, it transforms to amorphous state and carbon onions. The reduction of infrared reflectivity in the severely sheared phase indicates the decrease in conductivity. Our results unveil the shear sensitive nature of graphene, point out the effects of shear on its physical properties, and provide a potential method to manipulate this promising material. [ABSTRACT FROM AUTHOR]

The adoption of high pressure not only reinforces the comprehension of the structure and exotic electronic states of transition metal dichalcogenides (TMDs) but also promotes the discovery of intriguing phenomena. Here, 1T-TaS2 was investigated up to 100 GPa, and re-enhanced superconductivity was found with structural phase transitions. The discovered I4/mmm TaS2 presents strong electron–phonon coupling, revealing a good superconductivity of the nonlayered structure. The P–T phase diagram shows a dome shape centered at ~20 GPa, which is attributed to the distortion of the 1T structure. Accompanied by the transition to nonlayered structure above 44.5 GPa, the superconducting critical temperature shows an increasing trend and reaches ~7 K at the highest studied pressure, presenting superior superconductivity compared to the original layered structure. It is unexpected that the pressure-induced re-enhanced superconductivity was observed in TMDs, and the transition from a superconductor with complicated electron-pairing mechanism to a phonon-mediated superconductor would expand the field of pressure-modified superconductivity. [ABSTRACT FROM AUTHOR]

Ethylene is a gaseous hormone that affects many processes of plant growth and development. During vascular development, ethylene positively regulates cambial cell division in parallel with tracheary element differentiation inhibitory factor (TDIF) peptide signaling. In this study, we identified an ethylene overproducing mutant, acs7-d , exhibiting enhanced cambial activity and reduced wall development in fiber cells. Using genetic analysis, we found that ethylene signaling is necessary for the phenotypes of enhanced cambial cell division as well as defects in stem elongation and fiber cell wall development. Further, the cambial cell proliferation phenotype of acs7-d depends on WOX4, indicating that the two parallel pathways, ethylene and TDIF signaling, converge at WOX4 in regulating cambium activity. Gene expression analysis showed that ethylene impedes fiber cell wall biosynthesis through a conserved hierarchical transcriptional regulation. These results advance our understanding of the molecular mechanisms of ethylene in regulating vascular meristem activity. [ABSTRACT FROM AUTHOR]

A polyester filament winding spindle is the most complex winding rotor system, due to its high speed, heavy load, and frequency-dependent parameters; furthermore, the spindle's rotating speed constantly changes and it is continually crossing the critical speed points. This paper presents an approach to establish the finite element model of the winding spindle to predict its dynamic behavior characteristics during start-up. Firstly, three finite element models of the discrete single component were developed based on the Timoshenko beam theory. The bending, transverse shear effect, and gyroscopic moment were considered in these models. The flexible supporting system, which consists of a deep groove ball bearing and several rubber O-rings, is simplified by a nonlinear spring and damper. Its frequency-dependent dynamic supporting parameters are identified by experiment. Secondly, a fully dynamic model of the polyester winding spindle system, which consists of the cantilever supporting arm, shaft, and sleeve, as well as the flexible and rigid coupling elements, was established. Thirdly, the Newmark method was used to develop a program for solving the dynamic equations of the spindle system in MATLAB®. Based on the model of the spindle system and the computation program, the effects of the supporting stiffness, damping, and start-up time on the spindle's unbalanced response were investigated. The results indicate that the model of the spindle system presented in this paper is suitable for the prediction of the dynamic performance during its start-up. [ABSTRACT FROM AUTHOR]

A filament bundle is a kind of filament assembly with less twist or nontwist. It is a viscoelastic body and has a large aspect ratio. Its large deformation during motion over a wide range is a universal phenomenon in many textile processes. The dynamic viscoelasticity of the filament bundle, gravity, and air resistance are three important factors affecting the filament bundle's dynamic behavior. Taking account of these factors, a filament bundle dynamics analysis method is proposed in a series of three papers. This paper, the first in the series, presents an approach to model the dynamics of the flexible filament bundle with viscoelasticity and to analyze its dynamic behavior under the action of gravity and air resistance. The filament bundle element (FBE) is established based on absolute nodal coordinate formulation (ANCF), in which slope vectors and global coordinates are applied. The approach presented in this paper is well suited for the analysis of large deformation motions of filament bundles. As an example, a dynamic model was established to predict the filament bundle's trace during its swinging through large displacements under the action of gravity and air resistance, taking into account the filament bundle viscosity. The nonlinear differential equations of the filament bundle system were solved using MATLAB. Furthermore, the swing traces of the filament bundle in a closed Plexiglas box with different vacuum degrees were recorded using a high-speed camera to prove the validity of the established filament bundle model based on ANCF. [ABSTRACT FROM AUTHOR]

A new finite element dynamic model of a moving yarn segment has been proposed in this paper based on the absolute nodal coordinate formulation (ANCF). Apart from taking into account the elastic properties of the yarn in three dimensions, the model also considers the viscosity in the longitudinal direction and takes into account the effect of gravity and air resistance. In this paper, the simulation described the movement of the yarn segment that is pulled by the fixer on the guideway. Then, a corresponding experiment was proposed to evaluate the theoretical model. The theoretical and experimental comparisons of the motion tracing exhibited good agreement, demonstrating that the new model could predict the actual moving trace of the yarn segment. Moreover, another simulation of the spatial motion of the yarn segment was presented, to elucidate the role of the model in predicting the movement of the yarn segment. After considering the parameters of the actual process and its constraints, the authors established that the proposed model could be used to predict the trajectory of a yarn segment in the actual production process, which is vital when fabricating textile products. [ABSTRACT FROM AUTHOR]

Core-shell structured quantum dot (QD)-silica fluorescent nanoparticles have attracted a great deal of attention due to the excellent optical properties of QDs and the stability of silica. In this study, core-shell structured CdTe/CdS@SiO2@CdTe@SiO2 fluorescent nanospheres were synthesized based on the Stöber method using multistep silica encapsulation. The second silica layer on the CdTe QDs maintained the optical stability of nanospheres and decreased adverse influences on the probe during subsequent processing. Red-emissive CdTe/CdS QDs (630 nm) were used as a built-in reference signal and green-emissive CdTe QDs (550 nm) were used as a responding probe. The fluorescence of CdTe QDs was greatly quenched by added S2−, owing to a S2−-induced change in the CdTe QDs surface state in the shell. Upon addition of Cd2+ to the S2−-quenched CdTe/CdS@SiO2@CdTe@SiO2 system, the responding signal at 550 nm was dramatically restored, whereas the emission at 630 nm remained almost unchanged; this response could be used as a ratiometric 'off-on' fluorescent probe for the detection of Cd2+. The sensing mechanism was suggested to be: the newly formed CdS-like cluster with a higher band gap facilitated exciton/hole recombination and effectively enhanced the fluorescence of the CdTe QDs. The proposed probe shows a highly sensitive and selective response to Cd2+ and has potential application in the detection of Cd2+ in environmental or biological samples. [ABSTRACT FROM AUTHOR]

Emerging evidences exhibit that mitogen-activated protein kinase (MAPK/MPK) signaling pathways are connected with many aspects of plant development. The complexity of MAPK cascades raises challenges not only to identify the MAPK module in planta but also to define the specific role of an individual module. So far, our knowledge of MAPK signaling has been largely restricted to a small subset of MAPK cascades. Our previous study has characterized an Arabidopsis bushy and dwarf1 (bud1) mutant, in which the MAP Kinase Kinase 7 (MKK7) was constitutively activated, resulting in multiple phenotypic alterations. In this study, we found that MPK3 and MPK6 are the substrates for phosphorylation by MKK7 in planta. Genetic analysis showed that MKK7-MPK6 cascade is specifically responsible for the regulation of shoot branching, hypocotyl gravitropism, filament elongation, and lateral root formation, while MKK7-MPK3 cascade is mainly involved in leaf morphology. We further demonstrated that the MKK7-MPK6 cascade controls shoot branching by phosphorylating Ser 337 on PIN1, which affects the basal localization of PIN1 in xylem parenchyma cells and polar auxin transport in the primary stem. Our results not only specify the functions of the MKK7-MPK6 cascade but also reveal a novel mechanism for PIN1 phosphorylation, establishing a molecular link between the MAPK cascade and auxin-regulated plant development. [ABSTRACT FROM AUTHOR]

Correction for 'A morphology-dependent lattice stability investigation in ZnS nanostructures by high-pressure XAFS studies' by Qing Dong et al., J. Mater. Chem. C, 2022, https://doi.org/10.1039/d2tc02043b. [ABSTRACT FROM AUTHOR]

Arabidopsis thaliana WRKY39, a transcription factor that is induced by heat stress, is a member of the group II WRKY proteins and responds to both abiotic and biotic stress. Heat-treated seeds and plants of WRKY39 knock-down mutants had increased susceptibility to heat stress, showing reduced germination, decreased survival, and elevated electrolyte leakage compared with wild-type plants. In contrast, WRKY39 over-expressing plants exhibited enhanced thermotolerance compared with wild-type plants. RT-PCR and qRT-PCR analysis of wrky39 mutants and WRKY39 over-expressing plants identified putative genes regulated by WRKY39. Consistent with a role for WRKY39 in heat tolerance, the expression levels of salicylic acid (SA)-regulated PR1 and SA-related MBF1c genes were downregulated in wrky39 mutants. In contrast, over-expression of WRKY39 increased the expression of PR1 and MBF1c. The WRKY39 transcript was induced in response to treatment with SA or methyljasmonate. Analysis of heat stress-induced WRKY39 in defense signaling mutants, including coi1, ein2, and sid2, further indicated that WRKY39 was positively co-regulated by the SA and jasmonate (JA) signaling pathways. Together, these findings reveal that heat stress-induced WRKY39 positively regulates the cooperation between the SA- and JA-activated signaling pathways that mediate responses to heat stress. [ABSTRACT FROM AUTHOR]

We identified a Nodulin-related protein 1 (NRP1) encoded by At2g03440, which was previously reported to be RPS2 interacting protein in yeast-two-hybrid assay. Northern blotting showed that AtNRP1 expression was suppressed by heat stress (42°C) and induced by low temperature (4°C) treatment. Strong GUS staining was observed in the sites of meristematic tissues of pAtNRP1:: GUS transgenic plants, such as shoot apex and root tips, young leaf veins, stamens and stigmas of flowers, and abscission layers of young siliques. To study AtNRP1 biological functions, we have characterized both loss-of-function T-DNA insertion and transgenic overexpression plants for AtNRP1 in Arabidopsis. The T-DNA insertion mutants displayed no obvious difference as compared to wild-type Arabidopsis under heat stress, but the significant enhanced susceptibility to heat stress was revealed in two independent AtNRP1-overexpressing transgenic lines. Further study found that the decreased thermtolerance in AtNRP1-overexpressing lines accompanied significantly decreased accumulation of ABA after heat treatment, which was probably due to AtNRP1 playing a role in negative-feedback regulation of the ABA synthesis pathway. These results support the viewpoint that the application of ABA inhibits nodulation and nodulin-related gene expression and threaten adverse ambient temperature can impact the nodulin-related gene expression. [ABSTRACT FROM AUTHOR]

[EtN] [Co(NHCSNHNH)] [MoO] ·4MeNCHO, obtained by reacting MoCl, CoCl, thiosemicarbazide and DMF in nonaqueous solvents under i.r. radiation, was characterized by spectroscopy and X-ray crystallography. It contains an octanuclear molydenum anion with two pentabridging oxygen atoms and a cobalt-centred cation bonded to nitrogen and sulphur ligands. [ABSTRACT FROM AUTHOR]