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We study the Cauchy problem for the Davey-Stewartson equation $${\rm{i}}{\partial _t}u + \Delta u + {\left| u \right|^2}u + {E_1}({\left| u \right|^2})u = 0,\,\,\,\,\,\,(t,x) \in \mathbb{R} \times {\mathbb{R}^3}.$$ The dichotomy between scattering and finite time blow-up shall be proved for initial data with finite variance and with mass-energy M(u0)E(u0) above the ground state threshold M(Q)E(Q).

In this paper, we study the spectrality of Sierpinski-Moran measure defined as an infinite convolution measure: $$\begin{aligned} \mu _{\{M_j\},\{{\mathcal {D}}_j\}}=\delta _{M_1^{-1}{\mathcal {D}}_1}*\delta _{(M_1M_2)^{-1}{\mathcal {D}}_2}*\cdots , \end{aligned}$$ where $${\mathcal {D}}_n=\{(0,0)^t,(a_n,0)^t,(0,b_n)^t\}\subset {\mathbb {Z}}^{2}$$ and $$\;M_n=\text {diag}(s_n,t_n)\in M_2(\mathbb Z)$$ are $$2\times 2$$ expanding diagonal matrices. Our goal is to investigate the existence of Fourier orthonormal basis for $$L^2(\mu _{\{M_n\},\{{\mathcal {D}}_n\}})$$ , i.e., find an exponential function system $$\{e^{2\pi i\langle \lambda ,x \rangle }\}_{\lambda \in \Lambda }$$ forming an orthonormal basis for $$L^2(\mu _{\{M_n\},\{{\mathcal {D}}_n\}})$$ . Some sufficient conditions for this aim are given, and some spectra $$\Lambda $$ are found.

Wearable electronics, as essential components of the Internet of Things (IoT), have attracted widespread attention, and the trend is to configure attractive wearable smart microsystems by integrating sensing, powering, and other functions. Herein, we developed an elastic hybrid triboelectric–electromagnetic microenergy harvester (named EHTE) to realize hybrid sensing and microenergy simultaneously. This EHTE is a highly integrated triboelectric nanogenerator (TENG) and electromagnetic nanogenerator (EMG). Based on the triboelectric–electromagnetic hybrid mechanism, an enhanced electrical output of the EHTE was achieved successfully, which demonstrates the feasibility of the EHTE for microelectronics powering. Moreover, with the merits of the EMG, the developed hybrid microenergy harvester integrated both active frequency sensing and passive inductive sensing capabilities. Specifically, the almost linear correlation of the electromagnetic outputs to the frequencies of the external stimulus endowed the proposed EHTE with an outstanding active frequency sensing ability. In addition, due to the unique structural configuration of the EMG (i.e., a conductive permanent magnet (PM), hybrid deformation layer, and flexible printed circuit board (FPCB) coil), an opportunity was provided for the developed EHTE to serve as a passive inductive sensor based on the eddy current effect (i.e., a form of electromagnetic induction). Therefore, the developed EHTE successfully achieved the integration of hybrid sensing (i.e., active frequency sensing and passive inductive sensing) and microenergy (i.e., the combination of electromagnetic effect and triboelectric effect) within a single device, which demonstrates the potential of this newly developed EHTE for wearable electronic applications, especially in applications of compact active microsystems.

Abrading is a very important sub-technology of the surface treatment technology with vast applications in the industry. This study aims at analyzing the inherent laws of friction systems during abrading. In particle flow code modeling, the abrading process can be simplified to the movement of particles in a parallel-plate shear friction system. In this study, the PFC2D software is used to construct the particle flow friction system with the set of parallel plates and the model parameters according to the abrading processing equipment and processing materials, control the simulation of a single variable, and compare the output data to estimate the impact of change of parameters on the force chain. The simulation results show that the shear dilatancy can be divided into three stages: plastic strain, macroscopic failure, and granular recombination stages. The distribution and load rates of the weak force chains depend on the load, velocity, friction coefficient between granules, granular diameter, and number of granular layers. The number of granular layers and the load increase cause the direction of the force chain to be oriented with the vertical direction, and the force chains move toward the horizontal direction as the velocity increases. The increase in load does not cause the shear dilatancy stage to occur; the velocity, friction coefficient between granules, and granular diameter increase cause the shear dilatancy to occur gradually.

Soybean is a widely grown grain legume and one of the most important economic crop species. Brassinosteroids play a crucial role in plant vegetative growth and reproductive development. However, it remains unclear how BRs regulate the developmental processes in soybean, and the molecular mechanism underlying soybean early development is largely unexplored. In this study, we first characterized how soybean early vegetative growth was specifically regulated by the BR biosynthesis inhibitor propiconazole; this characterization included shortened root and shoot lengths, reduced leaf area, and decreased chlorophyll content. In addition, the growth inhibition induced by Pcz could be rescued by exogenous brassinolide application. The RNA-seq technique was employed to investigate the BR regulatory networks during soybean early vegetative development. Identification and analysis of differentially expressed genes indicated that BRs orchestrate a wide range of cellular activities and biological processes in soybean under various BR concentrations. The regulatory networks between BRs and multiple hormones or stress-related pathways were investigated. The results provide a comprehensive view of the physiological functions of BRs and new insights into the molecular mechanisms at the transcriptional level of BR regulation of soybean early development.

Background Brassinosteroids (BRs) play a crucial role in plant vegetative growth and reproductive development. The transcription factors BZR1 and BES1/BZR2 are well characterized as downstream regulators of the BR signaling pathway in Arabidopsis and rice. Soybean contains four BZR1-like proteins (GmBZLs), and it was reported that GmBZL2 plays a conserved role in BR signaling regulation. However, the roles of other GmBZLs have not been thoroughly studied, and the targets of GmBZLs in soybean remain unclear. Results In this study, we first characterized GmBZL3 in soybean from gene expression patterns, conserved domains in coding sequences, and genomic replication times of four GmBZL orthologous. The results indicated that GmBZL3 might play conserved roles during soybean development. The overexpression of GmBZL3P219L in the Arabidopsis BR-insensitive mutant bri1–5 partially rescued the phenotypic defects including BR-insensitivity, which provides further evidence that GmBZL3 functions are conserved between soybean and the homologous Arabidopsis genes. In addition, the identification of the GmBZL3 target genes through ChIP-seq technology revealed that BR has broad roles in soybean and regulates multiple pathways, including other hormone signaling, disease-related, and immunity response pathways. Moreover, the BR-regulated GmBZL3 target genes were further identified, and the results demonstrate that GmBZL3 is a major transcription factor responsible for BR-regulated gene expression and soybean growth. A comparison of GmBZL3 and AtBZR1/BES1 targets demonstrated that GmBZL3 might play conserved as well as specific roles in the soybean BR signaling network. Finally, the identification of two natural soybean varieties of the GmBZL3 mutantion by SNP analysis could facilitate the understanding of gene function during soybean development in the future. Conclusions We illustrate here that GmBZL3 orchestrates a genome-wide transcriptional response that underlies BR-mediated soybean early vegetative growth, and our results support that BRs play crucial regulatory roles in soybean morphology and gene expression levels. Electronic supplementary material The online version of this article (10.1186/s12870-019-1677-2) contains supplementary material, which is available to authorized users.

In 2009, the draft genome of the reference inbred line of maize (Zea mays L. spp. mays cv. B73) was published so that, using this specific corn variety, molecular analyses of physiological processes became possible. However, the morphology and developmental patterns of B73 maize, compared with that of the more frequently used hybrid varieties, have not yet been analyzed. Here, we describe organ development in seedlings of B73 maize and in those of six other hybrid cultivars, and document significant morphological as well as quantitative differences between these varieties of Z. mays. In a second set of experiments, we used etiolated seedlings of B73 maize to analyze the effect of blue light (BL) on the patterns of proteins in the tip vs. growing region of this sheath-like organ. By using two-dimensional difference gel electrophoresis (2D DIGE), coupled with tandem mass spectrometry, we detected, in the microsomal fraction of maize coleoptile tips, rapid changes in the abundance of protein spots of maize phototropin 1 and several metabolic enzymes. In the sub-apical (growing) region of the coleoptile, proteomic changes were less pronounced. These results suggest that the tip of the coleoptile of B73 maize may serve as a unique model system for dissecting BL responses in a light-sensitive plant organ of known function.

SWI/SNF-type chromatin remodelers, such as BRAHMA (BRM), and H3K27 demethylases both have active roles in regulating gene expression at the chromatin level1–5, but how they are recruited to specific genomic sites remains largely unknown. Here we show that RELATIVE OF EARLY FLOWERING 6 (REF6), a plant-unique H3K27 demethylase6, targets genomic loci containing a CTCTGYTY motif via its zinc-finger (ZnF) domains and facilitates the recruitment of BRM. Genome-wide analyses showed that REF6 colocalizes with BRM at many genomic sites with the CTCTGYTY motif. Loss of REF6 results in decreased BRM occupancy at BRM–REF6 co-targets. Furthermore, REF6 directly binds to the CTCTGYTY motif in vitro, and deletion of the motif from a target gene renders it inaccessible to REF6 in vivo. Finally, we show that, when its ZnF domains are deleted, REF6 loses its genomic targeting ability. Thus, our work identifies a new genomic targeting mechanism for an H3K27 demethylase and demonstrates its key role in recruiting the BRM chromatin remodeler.

Hydrogen peroxide (H2O2) is an important signaling molecule in plant developmental processes and stress responses. However, whether H2O2-mediated signaling crosstalks with plant hormone signaling is largely unclear. Here, we show that H2O2 induces the oxidation of the BRASSINAZOLE-RESISTANT1 (BZR1) transcription factor, which functions as a master regulator of brassinosteroid (BR) signaling. Oxidative modification enhances BZR1 transcriptional activity by promoting its interaction with key regulators in the auxin-signaling and light-signaling pathways, including AUXIN RESPONSE FACTOR6 (ARF6) and PHYTOCHROME INTERACTING FACTOR4 (PIF4). Genome-wide analysis shows that H2O2-dependent regulation of BZR1 activity plays a major role in modifying gene expression related to several BR-mediated biological processes. Furthermore, we show that the thioredoxin TRXh5 can interact with BZR1 and catalyzes its reduction. We conclude that reversible oxidation of BZR1 connects H2O2-mediated and thioredoxin-mediated redox signaling to BR signaling to regulate plant development., Hydrogen peroxide and brassinosteroids (BR) both regulate plant development and stress responses. Here Tian et al. show that hydrogen peroxide can trigger oxidation of the BR-responsive BZR1 transcription factor and promote its transcriptional activity, thereby linking BR and redox signaling.

Amplified fragment length polymorphism markers were used to estimate the genetic divergence and genetic structure of Lateolabrax maculatus, L. japonicus and their possible hybrid populations in the Northwestern Pacific. Ninety one individuals were sampled from nine localities including two putative hybrid samples across the distribution range of the two species. Five primer combinations generated a total of 423 loci among 91 individuals of L. maculatus and L. japonicus, 266 of which were polymorphic (62.88 %). The percentage of polymorphic loci in three populations of L. maculatus and five populations of L. japonicus ranged from 31.96 % (Beihai) to 37.94 % (Weihai), 31.05 % (Ishikawa) to 49.29 % (Yatsushiro Sea), respectively. The UPGMA tree constructed with individuals of both species indicated reciprocal monophyletic relationship between L. japonicus and L. maculatus. Hybrid individuals between the two species in Ariake Sea and Yatsushiro Sea were identified by UPGMA tree and principal component analysis (PCA). The sympatry of two clades in the Yatsushiro Sea gave the first evidence of possible reproductive isolation between hybrid and L. japonicus. AMOVA analysis and pairwise F ST revealed significant genetic differentiation within both species, indicating limited dispersal ability in two species. Historical isolation coupled with low dispersal ability was responsible for the genetic divergence between species and significant genetic structure in the two species.

Large yellow croaker (Larimichthys crocea) is an important maricultured species in China. A genetic linkage map of the large yellow croaker was constructed using type II microsatellites and expressed sequence tag (EST)-derived microsatellites in two half-sib families (two females and one male). A total of 289 microsatellite markers (contained 93 EST-SSRs) were integrated into 24 linkage groups, which agreed with the haploid chromosome number. The map spanned a length of 1,430.8 cm with an average interval of 5.4 cm, covering 83.9 % of the estimated genome size (1,704.8 cm). A total of seven quantitative trait locis (QTLs) were detected for growth traits on five linkage groups, including two 1 % and five 5 % chromosome-wide significant QTLs, and explained from 2.33 to 5.31 % of the trait variation. The identified QTLs can be applied in marker-assisted selection programs to improve the growth traits.

Electrical current induced heat generation through an ultrasmall quantum dot–leads coupled system under AC fields is investigated by employing the nonequilibrium Green’s function technique. The external AC fields, charging energy and junction capacitances influence the heat generation sensitively. We find negative differential heat generation in our system. The reason for this is the Coulomb interaction, and the negative differential heat generation becomes larger as the frequency of AC fields $$\omega $$ increases. In addition, the peak caused by charging energy in $$Q{/}\omega _0$$ curve increases with $$\omega $$ rapidly. A region in which the value $$Q{/}I$$ is low emerges due to the charging effect. It is an ideal region for device operation. This region will enlarge as the parameter $$R$$ and the charging energy $$E_c$$ increase.

Plant GSK3-like kinases are key regulators that modulate a broad range of physiological processes such as cell growth, stomatal and flower development, responses for abiotic and biotic stress, and carbohydrate metabolism. Arabidopsis Shaggy/GSK3-like kinases (AtSK) consist of ten members that are classified into four subfamilies (I∼IV). Only one of these Arabidopsis GSK3s, BIN2 (also named AtSK21), has been characterized by biochemical and genetic studies. BIN2 acts as a negative regulator in brassinosteroid (BR) signaling that controls cell growth and differentiation. Recent studies suggest that at least seven AtSKs are involved in BR signaling. However, specificities for the substrates and the functional differences of each member of the family remain to be determined. Here we report structural characteristics and distinct function of AtSK12 compared with BIN2. AtSK12 has a longer N-terminal extension, which is absent in BIN2. Transgenic plants overexpressing the AtSK12 mutant carrying deletion of N-terminal region display more severe dwarf phenotypes than those of the wild-type AtSK12. Microscopic analysis reveals that N-terminal-deleted AtSK12 accumulates in the nucleus. This implies that structural difference in the N-terminal region of AtSK members contributes to their subcellular localization. In contrast to BIN2, overexpression of AtSK12 does not cause a stomatal cluster. Furthermore, we show that YODA MAPKKK, which controls stomatal development, interacts with BIN2 but not with AtSK12. Our results suggest that AtSK12 mediates BR-regulated cell growth but not stomatal development while BIN2 regulates both processes. Our study provides evidence that different GSK3 members can have overlapping but non-identical functions.

Previous studies have shown that endothelial colony forming cells (ECFCs) play an important role in the neovascularization of tumors. Hypoxia is emphasized as an important promoter of angiogenesis. However, little is known about genome-wide transcriptional regulation of ECFCs under hypoxic conditions. In this study, gene expression profiles in ECFCs were evaluated under hypoxic conditions for 3, 6, 12, 24, and 48 h, using Affymetrix U133 plus 2.0 chip microarray. 1,103 hypoxia-regulated genes were filtered, with 379 (0.693 %) genes up-regulated and 724 (1.32 %) genes down-regulated. Most of the up-regulated genes were involved in apoptosis, cell proliferation, or metabolic processes, while most of the down-regulated genes were involved in cell adherence, cell cycle, DNA and mRNA metabolic processes, multi-cellular organism development, protein metabolic processes, response to stress, signal transduction, or transport. This expression profile is ECFC-specific, because it is significantly different from those of endothelial cells and smooth muscle cells under hypoxic conditions. Moreover, hypoxia-regulated apoptosis in ECFCs is mainly related with the mitochondrial pathway (p53-BAX-Caspase-9) and the death receptor pathway (FAS-Caspase-8-Caspase-3). MAPK pathway is activated in ECFCs under hypoxic conditions. The differentially expressed genes of ECFCs were identified under hypoxic conditions, and related with cell apoptosis, cell cycle and MAPK pathways, shedding light on the mechanism of angiogenesis.

The bacterial tobacco wilt caused by Ralstonia solanacearum is one of the most destructive soil-borne diseases worldwide. One strategy to improve the resistance to bacterial wilt is to make use of plant varieties expressing wilt resistance genes. To characterize the genetics of wilt resistance and to identify relevant molecular markers for use in plant breeding, quantitative trait loci (QTLs) affecting tobacco bacterial wilt resistance were mapped in the F2:3 and F2:4 progeny produced from two crosses between the wilt-resistant breeding lines Enshu and Yanyan97 and the susceptible cultivar TI448A. A linkage map containing 118 loci in 24 linkage groups was constructed for 236 lines from the Enshu×TI448A cross, and a linkage map containing 96 loci in 24 linkage groups was constructed for 264 lines from the Yanyan97×TI448A cross. The wilt resistance of the progeny was examined in field trials conducted in Xuancheng, China, in 2010, 2011, and 2012. The disease severity was assessed on stems using separate rating scales. Mapmaker/EXP 3.0 and Mapmaker/QTL 1.1 were used to identify the qBWR-3a, qBWR-3b, qBWR-5a and qBWR-5b QTLs in linkage group 3 and 5; these four loci were strongly associated with resistance and explain 9.00, 19.70, 17.30, and 17.40 % of the variance in resistance, respectively. The close linkage of the markers PT20275 and PT30229 was detected in both the TI448A×Enshu and TI448A×Yanyan97 crosses, and this linkage group could be used to select individual resistant plants. These findings suggest that one strategy to combat bacterial wilt could be to exploit the resistance genes of the Enshu and Yanyan97 strains.

Structural basis for the impact of phosphorylation on the activation of plant receptor-like kinase BAK1

Plants must coordinate the regulation of biochemistry and anatomy to optimize photosynthesis and water-use efficiency. The formation of stomata, epidermal pores that facilitate gas exchange, is highly coordinated with other aspects of photosynthetic development. The signalling pathways controlling stomata development are not fully understood, although mitogen-activated protein kinase (MAPK) signalling is known to have key roles. Here we demonstrate in Arabidopsis that brassinosteroid regulates stomatal development by activating the MAPK kinase kinase (MAPKKK) YDA (also known as YODA). Genetic analyses indicate that receptor kinase-mediated brassinosteroid signalling inhibits stomatal development through the glycogen synthase kinase 3 (GSK3)-like kinase BIN2, and BIN2 acts upstream of YDA but downstream of the ERECTA family of receptor kinases. Complementary in vitro and in vivo assays show that BIN2 phosphorylates YDA to inhibit YDA phosphorylation of its substrate MKK4, and that activities of downstream MAPKs are reduced in brassinosteroid-deficient mutants but increased by treatment with either brassinosteroid or GSK3-kinase inhibitor. Our results indicate that brassinosteroid inhibits stomatal development by alleviating GSK3-mediated inhibition of this MAPK module, providing two key links; that of a plant MAPKKK to its upstream regulators and of brassinosteroid to a specific developmental output.

Brassinosteroids are essential phytohormones that have crucial roles in plant growth and development. Perception of brassinosteroids requires an active complex of BRASSINOSTEROID-INSENSITIVE 1 (BRI1) and BRI1-ASSOCIATED KINASE 1 (BAK1). Recognized by the extracellular leucine-rich repeat (LRR) domain of BRI1, brassinosteroids induce a phosphorylation-mediated cascade to regulate gene expression. Here we present the crystal structures of BRI1(LRR) in free and brassinolide-bound forms. BRI1(LRR) exists as a monomer in crystals and solution independent of brassinolide. It comprises a helical solenoid structure that accommodates a separate insertion domain at its concave surface. Sandwiched between them, brassinolide binds to a hydrophobicity-dominating surface groove on BRI1(LRR). Brassinolide recognition by BRI1(LRR) is through an induced-fit mechanism involving stabilization of two interdomain loops that creates a pronounced non-polar surface groove for the hormone binding. Together, our results define the molecular mechanisms by which BRI1 recognizes brassinosteroids and provide insight into brassinosteroid-induced BRI1 activation.

Brassinosteroid (BR) regulates gene expression and plant development through a receptor kinase-mediated signal transduction pathway. Despite the identification of many components of this pathway, it remains unclear how the BR signal is transduced from the cell surface to the nucleus. Here we describe a complete BR signalling pathway by elucidating key missing steps. We show that phosphorylation of BSK1 (BR-signalling kinase 1) by the BR receptor kinase BRI1 (BR-insensitive 1) promotes BSK1 binding to the BSU1 (BRI1 suppressor 1) phosphatase, and BSU1 inactivates the GSK3-like kinase BIN2 (BR-insensitive 2) by dephosphorylating a conserved phospho-tyrosine residue (pTyr 200). Mutations that affect phosphorylation/dephosphorylation of BIN2 pTyr200 (bin2-1, bin2-Y200F and quadruple loss-of-function of BSU1-related phosphatases) support an essential role for BSU1-mediated BIN2 dephosphorylation in BR-dependent plant growth. These results demonstrate direct sequential BR activation of BRI1, BSK1 and BSU1, and inactivation of BIN2, leading to accumulation of unphosphorylated BZR (brassinazole resistant) transcription factors in the nucleus. This study establishes a fully connected BR signalling pathway and provides new insights into the mechanism of GSK3 regulation.

This study reports an Agrobacterium-mediated transformation of green-colored cotton (Gossypium hirsutum L.). A tissue culture procedure was optimized to induce callus formation from hypocotyl explants and subsequent differentiation into the embryogenic type. Callus formation could be induced by growing explants on Murashige and Skoog medium containing 2,4-dichlorophenoxyacetic acid and kinetin. Among the four genotypes studied, embryogenic calli and plant regeneration were observed only in var. G9803. Agrobacterium-mediated transformation of G9803 with the fiber-specific expansin gene GhExpl was achieved based on the establishment of these tissue culture methods. A total of 32 individual regenerants resistant to kanamycin were generated within 7 mo., with a transformation frequency of 17.8%. Transformation was confirmed by Southern blot analysis and RT-PCR. These results represent the first step towards genetic manipulation of the colors and fiber quality of green-colored cottons by biotechnology.

Brassinosteroid (BR) regulates plant development by activating the transcription factor brassinazole resistant 1 (BZR1), which activates and represses different target genes to switch cellular programmes. The mechanisms that determine BZR1's transcriptional activities remain largely unknown. Here we show that BZR1 represses target genes by recruiting the Groucho/TUP1-like transcriptional corepressor TOPLESS (TPL). Specific deletion or mutation of an evolutionarily conserved ERF-associated amphiphilic repression (EAR) motif at the carboxy terminus abolishes BZR1's abilities to regulate gene expression and cell elongation, but these defects are rescued by TPL fusion to the EAR motif-mutated BZR1. The EAR motif in BZR1 mediates recruitment of TPL to BZR1-repressed promoters. A triple tpl mutant (tpl;tpr1;tpr4) shows reduced BR sensitivity and suppresses the gain-of-function bzr1-1D mutant phenotype. BR repression of gene expression also requires histone deacetylases that interact with TPL. Our study demonstrates key roles of the EAR motif and TPL in BR regulation of gene expression and plant growth.

Most multicellular organisms use steroids as signalling molecules for physiological and developmental regulation. Two different modes of steroid action have been described in animal systems: the well-studied gene regulation response mediated by nuclear receptors, and the rapid non-genomic responses mediated by proposed membrane-bound receptors. Plant genomes do not seem to encode members of the nuclear receptor superfamily. However, a transmembrane receptor kinase, brassinosteroid-insensitive1 (BRI1), has been implicated in brassinosteroid responses. Here we show that BRI1 functions as a receptor of brassinolide, the most active brassinosteroid. The number of brassinolide-binding sites and the degree of response to brassinolide depend on the level of BRI1 protein. The brassinolide-binding activity co-immunoprecipitates with BRI1, and requires a functional BRI1 extracellular domain. Moreover, treatment of Arabidopsis seedlings with brassinolide induces autophosphorylation of BRI1, which, together with our binding studies, shows that BRI1 is a receptor kinase that transduces steroid signals across the plasma membrane.

Constant strain rate compression tests at the temperature 900∼1100 °C and the strain rate 10−3∼20 s−1 and the interpass time 300∼1000 s of double stage interrupted tests were carried out for a microalloyed steel containing 0.024 % Nb, 0.016 % Ti, 1.39 % Mn and 0.15%C, to investigate its dynamic (DRX), static (SRX) and metadynamic recrystallization (MDRX) and precipitation behavior. Softening curves were determined by the offset method and back extrapolation method. It was found that the SRX and MDRX process have different Avrami exponent n and apparent activation energy Q. For the former n=1, Q=359 kJ/mol, while for the later n=0.57, Q=259 kJ/mol. Influences of temperature, prestrain and strain rate on the kinetics of SRX process were discussed and a mathematical model was furtherly constructed. Finally, the precipitation-time-temperature (PTT) curve was determined by the stress relaxation tests, and the influence of precipitation on the SRX process was also discussed. Direct microstructural evidence for precipitation during and after deformation was obtained by transmission electron microscopy.

Fe(x)/Mo(y), multilayered thin films (MLF) with y=7.0 nm and x=0.7, 1.3, 2.6, 3.6, 13.0 nm were fabricated by radio frequency (RF) sputtering. X-ray diffraction evidences that these films have a good periodicity and bcc structure for both Fe and Mo layers. Mossbauer spectra at room temperature (RT) are used to investigate the structure and the local magnetic properties of the interfaces between Fe and Mo layers. It is found that the interfaces present alloying features, i.e. the Fe atoms are randomly substituted by Mo atoms. Magnetic anisotropy which forces magnetic moments to lie in the film plane and reduced magnetic moments in interface region were observed. The specific magnetization of the films exhibits a BT3/2 dependence with very large values of B which can be attributed to the distribution of exchange interaction in the interfaces.