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Members of the R2R3-MYB4 subgroup are well-known negative regulatory transcription factors of phenylpropane and lignin pathways. In this study, we found that transgenic tobacco plants overexpressing a R2R3-MYB4 subgroup gene from Camellia sinensis (CsMYB4a) showed inhibited growth that was not regulated by phenylpropane and lignin pathways, and these plants exhibited altered sensitivity to synthetic auxin 1-naphthaleneacetic acid (α-NAA) treatment. An auxin/indole-3-acetic acid 4 (AUX/IAA4) gene from Camellia sinensis (CsIAA4) participating in the regulation of the auxin signal transduction pathway was screened from the yeast two-hybrid library with CsMYB4a as the bait protein, and tobacco plants overexpressing this gene showed a series of auxin-deficiency phenotypes, such as dwarfism, small leaves, reduced lateral roots, and a shorter primary root. CsIAA4 transgenic tobacco plants were less sensitive to exogenous α-NAA than control plants, which was consistent with the findings for CsMYB4a transgenic tobacco plants. The knockout of the endogenous NtIAA4 gene (a CsIAA4 homologous gene) in tobacco plants alleviated growth inhibition in CsMYB4a transgenic tobacco plants. Furthermore, protein–protein interaction experiments proved that domain II of CsIAA4 is the key motif for the interaction between CsIAA4 and CsMYB4a and that the degradation of CsIAA4 is prevented when CsMYB4a interacts with CsIAA4. In summary, our results suggest that CsMYB4a is a multifunctional transcription factor that regulates the auxin signaling pathway, phenylpropane and lignin pathways. This study provides new insights into the multiple functions of R2R3-MYB4 subgroup members as a group of well-known negative regulatory transcription factors.One-sentence summaryCsMYB4a act as multifunctional transcription factor that regulates the auxin signaling pathway, phenylpropane and lignin pathways.

Background Catechin protects heart from myocardial ischaemia/reperfusion (MI/R) injury. However, whether catechin inhibits H/R‐induced myocardial cell apoptosis is largely unknown. Objective This study aims to investigate the underlying mechanism of catechin in inhibiting the apoptosis of H/R‐induced myocardial cells. Methods LncRNA MIAT expression was detected by qRT‐PCR. Cell viability of H9C2 cells was detected using CCK‐8 assay. The apoptosis of H9C2 cells was detected by flow cytometry. The interaction between CREB and MIAT promoter regions was confirmed by dual‐luciferase reporter gene assay and ChIP assay. Results In MI/R rats, catechin improved heart function and down‐regulated lncRNA MIAT expression in myocardial tissue. In H/R‐induced H9C2 cells, catechin protected against cell apoptosis, and lncRNA MIAT overexpression attenuated this protective effect of catechin. We confirmed that transcription factor CREB could bind to MIAT promoter region, and catechin suppressed lncRNA MIAT expression through up‐regulating CREB. Catechin improved mitochondrial function and relieved apoptosis through promoting Akt/Gsk‐3β activation. In addition, MIAT inhibited Akt/Gsk‐3β activation and promoted cell apoptosis in H/R‐induced H9C2 cells. Finally, we found catechin promoted Akt/Gsk‐3β activation through inhibiting MIAT expression in H/R‐induced H9C2 cells. Conclusion Catechin relieved H/R‐induced myocardial cell apoptosis through regulating CREB/lncRNA MIAT/Akt/Gsk‐3β pathway.

Pinoresinol/lariciresinol reductase (PLR), an NADPH-dependent reductase that catalyzes the sequential reduction of pinoresinol into secoisolariciresinol via Lariciresinol, can lead to the structural and stereochemical diversity of lignans. The relationship between substrate-selective reaction of PLR and sequence homology still remains unclear. In this study, we focused on the contribution of the variable region between PLRs in determining substrate selectivity. Here, two CsPLRs (CsPLR1 and CsPLR2) were identified in the tea plant (Camellia sinensis var. sinensis cv. Shuchazao). In vitro enzymatic assays showed that CsPLR1 could convert (+)- and (−)-pinoresinol into lariciresinol or secoisolariciresinol, whereas CsPLR2 catalyzed (+)-pinoresinol enantioselectively into (−)-secoisolariciresinol. Homology modeling and site-directed mutagenesis were used to examine the role of a variable loop in catalysis and substrate selectivity. The L174I mutant in CsPLR1 lost the capacity to reduce either (+)- or (−)-pinoresinol but retained the ability to catalyze the reduction of (−)-lariciresinol. These findings provide a basis for better understanding of the substrate-selective reaction of PLR.

In this article, the functionally gradient materials and their preparation technology are rough expounded. Then, the technical requirements of gradient AlSi alloy in the field of aeronautical active phased array radar are indicated. After a brief analysis, it is pointed out that the methods above are not suitable for manufacturing gradient AlSi alloy. And the 3D printing additive manufacturing technology can be applied to prepare the gradient AlSi alloy. Through the optimization of laser melting deposition technology and the experimental process design, the AlSi alloy materials are prepared with the distribution of 73Al27Si, 62Al38Si, 50Al50Si, 62Al38Si, 73Al27Si, a total of gradient five layers. The microstructure and physical properties of the material are observed and tested respectively. It is shown that the material is compact without pores or cracks, and there are no pores or cracks at the interlaminar junction. The transition region between AlSi layers has obvious weld pool characteristic. From the test result, it can be seen that the fracture location is 50Al50Si body position. The tensile strength is above 140 MPa. After the temperature impact test and stress simulation, it is proved that the maximum stress value in the different gradient layers is far below the stress limit of the material itself, and the materials meet the requirements of the airborne environment. The physical properties change continuously with the continuous or quasi continuous changes of chemical composition. The T/R module boxes and electronic packaging structures are designed based on the gradient AlSi alloy. The integrated T/R module has also undergone environmental tests and screening validation at various product levels according to GJB 150A-2015 to prove the gradient AlSi alloy qualified. After the attempt of 3D printing laser melting deposition to prepare the gradient AlSi alloy, it is testified that the method and the material are reliable, following with further research in the preparation and basic problems.

A novel type of bi-constituent wire composite was obtained by combining melt-extracted Gd50Al30Co20 and Gd55Al20Co25 microwire components with Curie temperature (TC) of 86 K and 110 K, respectively. For a field change of 5 T, the wire composite possesses a table-like feature spanning a temperature interval of 30 K with value of ∼8.6 J kg−1 K−1, and enhanced refrigerant capacity (RC) and relative cooling power (RCP) values of ∼680 J kg−1 and ∼863 J kg−1, respectively. The experimental results agree well with those calculated by a simple bi-composition model, demonstrating the possibility of designing wire-based composites with desirable magnetocaloric effects (MCE) for active magnetic refrigeration.

Gd50Al30Co20 wires show excellent magnetocaloric properties and high heat exchange rate due to the microsize. The Weibull and lognormal methods were used for systematically analyzing its mechanical properties for matching the design requirements in cooling system. The wire exhibits average fracture strength of ~ 969.5 MPa and typical fracture behavior of amorphous character. Moreover, the distributions of stresses for tensile strains at 10 values are estimated by probability plot and Chi-square goodness-of-fit test. The random stresses were best fitted by lognormal probability distribution for most studied cases; however, fracture strength was best fitted by Weibull probability distribution. It is interesting to note that the mean and standard deviation of the stresses (to reach specific tensile strain) increase as the tensile strain grows, accompanied by the coefficients of variation of stresses which decrease smoothly. It is concluded that the inhomogeneity of material does cause the scatter of stresses growth, and the scatter could be considerably large.

Two soft ferromagnetic Co68.25Fe4.25Si12.25B15.25 microwires with the same diameter of 50 ± 1 μm but different fabrication processes were placed in series and in parallel circuit configurations to investigate their giant magneto-impedance (GMI) responses in a frequency range of 1–100 MHz for low-field sensing applications. We show that, while the low-field GMI response is significantly reduced in the parallel configuration, it is greatly enhanced in the series connection. These results suggest that a highly sensitive GMI sensor can be designed by arranging multi-wires in a saw-shaped fashion to optimize the sensing area, and soldered together in series connection to maintain the excellent magnetic field sensitivity.

To determine the spray forming process parameters of 7075/Al–Si bimetallic gradient composite plate with two gas atomizers, a calculation model of the plate has been established by using the finite element software ANSYS. The effects of different motion trajectory, advance speed, swing cycle and spray center distance on shape, and silicon distribution of deposited plate have been simulated by the APDL programming language. The results show that a smooth and uniform surface is obtained when motion trajectory is in a regular jaggies mode. The deposited plate varies from platform to stepped shape with a center distance increasing from 20 mm to 50 mm; meanwhile, the width of the transition zone decreases gradually. As the period increases to 8 s, the silicon distribution of each layer presents a jagged fluctuation. Both the thickness of the deposited plate and the width of the transition zone decrease as the advance speed increases, except the silicon distribution. Finally, the modeling and simulation of the co-spray formed 7075/Al–Si bimetallic gradient composite plate are validated by experimental investigations and the simulation results are in good agreement with the actual results.

Giant magnetocaloric effect in Ni-Mn-X (X=In, Sn, Sb) Heusler alloys has been revealed due to the significant shift of the martensite transformation temperatures under a bias magnetic field. However, the magnetic hysteresis during the magnetization and demagnetization cycles creates a large hysteresis loss and reduces the refrigeration capacity. Here we demonstrated that the magnetic hysteresis loss in Ni-Mn-Sb alloys was effectively reduced by Si-doping. The quaternary Ni 49.0 Mn 38.4 Sb 11.7 Si 0.9 alloy exhibited martensite and magnetic transitions around room temperature. Maximum magnetic entropy change Δ S m 9.4 J/kg K and working temperature interval 7.0 K were achieved attributed to the martensite transformation under a magnetic field of 5 T. Meanwhile, the average magnetic hysteresis loss for Ni 49.0 Mn 38.4 Sb 11.7 Si 0.9 alloy was 2.1 J/kg, much smaller than that for Ni 49.0 Mn 38.5 Sb 12.5 alloy, 11.4 J/kg. As a result, a refrigeration capacity of 50.2 J/kg was obtained in the Ni 49.0 Mn 38.4 Sb 11.7 Si 0.9 alloy. This result shows that Si-doped Ni-Mn-Sb alloys may act as a potential material system for magnetic refrigeration.

Techniques to fabricate patterned sapphire substrates (PSSs) have attracted much attention in recent decades. Wet etching behaviors and crystalline sapphire processes are critical for PSSs applications to improve the performance of light-emitting diodes. This study investigated the shape evolution behaviors and associated kinetics of cavities on the c-{0001} plane in crystalline sapphire during wet etching. It was revealed that wet etching reduces the cavity aspect ratio, and the cavity shape is a complicated structure constructed by 15 faceted planes of c-{0001}, r-{1 1 ¯ 02}, p-{11 2 ¯ 3}, m-{10 1 ¯ 0}, and s-{1 1 ¯ 01} families. A constant etching rate was demonstrated, suggesting the step flow mechanism of etching. The etching activation energy of crystalline sapphire is reduced by preformation of cavities as elucidated by the Arrhenius kinetic model followed during the etching process. This study provides new insight into wet etching behaviors of crystalline sapphire and might open up a way for fabricating sapphire substrate with large aspect ratio patterns.

Small-sized materials with large surface to volume ratio favor heat transfer during magnetic refrigeration cycling and thus may help enhancing the refrigeration efficiency. Here, high Fe content Ni44.9Fe4.3Mn38.3Sn12.5 polycrystalline microwires were prepared by a melt-extraction technique. The as-extracted microwires were annealed at 1173 K for 60 min, leading to significant grain growth and formation of a secondary Fe-rich γ phase. The annealed microwire exhibits larger magnetization difference (ΔM) between the austenite and martensite phases and smaller thermal hysteresis compared to the as-extracted microwire. The annealed microwire possesses a magnetic transition to austenite at 299 K, followed by a martensitic transformation (MT) from a ferromagnetic austenite to a weak-magnetic martensite at 208 K upon cooling. Under a magnetic field of 50 kOe, the annealed microwires show a maximum magnetic entropy change ΔSm of 6.9 J/kg·K and an effective refrigeration capacity RCeff of 78.0 J/kg over a broad working temperature span ΔTFWHM of 20 K around the MT. In addition, magnetic transition of the austenite gives rise to ΔSm −3.7 J/kg·K and RCmag 232.5 J/kg with ΔTFWHM of 85 K under 50 kOe. Keywords: Ferromagnetic shape memory alloys, Microwires, Martensitic transformation, Magnetocaloric effect, Ni-Fe-Mn-Sn

Ni-Mn-Sn alloys exhibit high magnetocaloric effect (MCE) during the magnetic-field-induced martensite to austenite phase transformation. However, the low magnetization of the austenite, narrow working temperature interval and high magnetic hysteresis reduced their magnetic refrigeration capacity. Here, the effects of Fe doping on the structural and magnetic transitions of Ni 50-x Fe x Mn 38 Sn 12 alloys were investigated. The doping of Fe higher than 2.9% induced the occurrence of a secondary γ phase, creating a dual phase alloy. The martensite transformation temperature significantly decreased with the occurrence of the secondary phase. However, the Curie temperatures of both austenite and martensite changed slightly with the formation of the secondary phase. As a result, the magnetostructural coupling, i.e. overlap of the structural and magnetic transitions between the ferromagnetic austenite and the paramagnetic martensite, occurred in the alloys with x = 0.5 - ∼4.2. Furthermore, the magnetization of the austenite and martensite both increased with increasing Fe content from x = 0 to x = 5.5, with the magnetization difference between the austenite and martensite saturating at x = 4.2. The dual phase Ni 45.8 Fe 4.2 Mn 38 Sn 12 alloy, exhibiting a magnetic field dependence of martensite transformation temperature ΔT M / μΔH - 0.28 K/kOe, showed a wider working temperature interval than that of the un-doped Ni 50 Mn 38 Sn 12 alloy. This demonstrated that the Ni 45.8 Fe 4.2 Mn 38 Sn 12 alloy might exhibit a high magnetic entropy change, wide working temperature interval and low magnetic hysteresis, and thus may be a promising magnetic refrigeration material.

Chemical wet etching technology is widely applied in semiconductor device fabrication such as the patterned sapphire substrates. However, the etching of pre-formed structure is still lack of investigations, which has potential applications in the preparation of particular devices. By using molten KOH etchant, the present work studied the wet etching behaviors of cavity on the A-plane of sapphire crystal in three-dimensional space and revealed the etching kinetics. It was demonstrated that the cavity will evolve into a complicate symmetric shape with multiple facet planes during etching. The width of the cavity is gradually expanded however the depth of the cavity is stable during etching, where the Arrhenius model was held, indicating that the etching process is realized by step flow removal of atoms. The present results improve the understanding of the morphology evolution and relevant kinetics of a pre-formed structure on sapphire crystal during wet etching, which shed further light on the single crystal wet etching technology for device fabrication.

We report upon the excellent magnetocaloric effect in melt-extracted DyHoCo medium entropy microwires. The magnetic entropy change (-ΔSM) reaches a large value of ∼11.2 J kg−1 K−1 for a field change (μ0ΔH) of 5 T. The large value of -ΔSM is resulted from the large magnetic moments of Dy and Ho. In addition, the DyHoCo microwires show a good cooling efficiency; RC1, RC2 and RC3 are evaluated to be ∼530 J kg−1, ∼417 J kg−1 and ∼279 J kg−1, respectively, at μ0ΔH = 5 T. The DyHoCo microwires undergo a second-order paramagnetic-ferromagnetic transition at the Curie temperature of ∼35 K. The excellent magnetocaloric property makes the melt-extracted DyHoCo microwires a promising refrigerant for cryogenic cooling application.

In this paper, the magnetocaloric effect (MCE) of a high-entropy Gd19Tb19Er18Fe19Al25 amorphous microwires fabricated by melt-extracted method are investigated systematically. These microwires exhibit a second-order phase transition from ferromagnetic to paramagnetic states at the Curie temperature of 97 K. The zero-field-cooling (ZFC) and field-cooling (FC) magnetization curves are irreversible when the temperature lower than the Curie temperature due to the spin glassy freezing behavior. The peak magnetic entropy change ( Δ S M pk ) for a field change from 0 to 5 T reaches ~5.94 J/kg∙K. In accordance to two criteria refrigerant capacity, the values of refrigerant capacity (RC) and relative cooling power (RCP) reach ~569 J/kg and ~733 J/kg at a field change of 5 T, respectively. These results suggest that the melt-extracted Gd19Tb19Er18Fe19Al25 microwires exhibit good MCE and have great potential to use as one kind of high temperature magnetic refrigeration material.

Ni45.6Fe3.6Mn38.4Sn12.4 microwires, with nanoscale γ-phase precipitates that enhance the magnetocaloric effects (MCEs) and mechanical properties, were prepared by a melt-extraction technique and subsequent high temperature annealing. The atomic ordering degree significantly increased after annealing, leading to a considerable increment in the structural entropy change (ΔStr) from 4.5 J/kg·K in the as-extracted microwire to 26.6 J/kg·K in the annealed one, and the magnetization difference (ΔM) from 35 A·m2/kg to 51 A·m2/kg under a magnetic field of 5.0 T. Consequently, a positive magnetic entropy change (ΔSM) peak of 15.2 J/kg·K with working temperature span (ΔTFWHM) of 12 K for the first-order martensite transformation followed by a negative ΔSM peak of −4.3 J/kg·K with ΔTFWHM = 50 K for the second-order magnetic transition under μ0ΔH = 5.0 T was achieved. By employing both magnetizing and demagnetizing processes for magnetic cooling, the two successive inverse and conventional MCEs in Ni–Fe–Mn–Sn microwires may show potential applications for micro-devices and systems.

Herein, we reported the influences of accumulated direct current annealing (ADA) on the GMI properties and microstructures of Zr-doped melt-extracted (Co 68.15 Fe 4.35 Si 12.25 B 12.25 Zr 3 ) amorphous microwires. There indicated that ADA-ed wires enhanced GMI properties and improved the microstructures remarkably in comparison with as-fabricated wires. The maximum GMI ratio [Δ Z / Z 0 ] max and equivalent magnetic circumferential anisotropy field (EMCAF) of ADA-ed microwires were increased to 256.01% and 4 Oe at 20 MHz, respectively, which are more than nearly 8 and 2 times of 33.62% and 1.6 Oe for as-fabricated wires, respectively. Moreover, the maximum magnetic field response sensitivity ( ξ max ) increased to 372.57%/Oe, which is much higher than the as-fabricated wires of 44.71%/Oe. The remarkable enhancement of GMI performance was considered as the microstructural evolution including structural relaxation, appearance of nano-crystallization, and circumferential arrangement of surface magnetic domains. Nano-crystallization degree and circumferential magnetic domains arrangement were effectively improved by actions of Joule thermal energy and circular magnetic field generated ADA as shown in HRTEM and magnetic force microscope (MFM) analysis. Based on above, both the excellent GMI performances and relatively large ξ max values indicate the ADA is an effective annealing technique for thermal treating the melt-extracted amorphous wires which applied for potentially magnetic sensor in detecting low-intensity magnetic fields.

Herein, we systematically studied the effect of a novel square-wave pulse current annealing (SPCA) on the magnetic properties and microstructure of Co-based melt-extracted amorphous wires, and efficiently tailored the related experimental parameters by using numerical calculation of transient temperature rise during SPCA process. We obtained the optimal SPCA treatment (at 50 Hz, with amplitude of 90 mA for 480 s) can remarkably enhance the GMI property of as-prepared wires. At 10 MHz, the maximum GMI ratio [Δ Z / Z 0 ] max and maxima response sensitivity ξ max of SPCA-treated wire increases to 202.60% and 305.74%/Oe, which is nearly two times and 1.5 times of 104.80% and 208.14%/Oe for as-cast wire, respectively. Especially, at 5 MHz, [Δ Z / Z 0 ] max of SPCA-treated wire increases to 185.81%, which is 2.5 times of 73.69% for as-cast wire, and ξ max of SPCA-treated wire increases to 346.65%/Oe by less than two times of 190.16%/Oe for as-cast wire. From mictrostructural perspective, the notably observed role of atomic order orientation regimes and circular magnetic domain during stress releasing or structural relaxation by the co-action of high-density pulse magnetic field energy and thermal activation energy determines the optimum efficiency of SPCA, further to enhance circumferential permeability. In conclusion, SPCA treatment is expected to effectively improve GMI property of microwires, which can be used as sensitive materials for potential sensor application in detecting weak magnetic field.

The effects of Fe doping on the microstructure, martensite transformation and superelasticity in melt-extracted Ni50Mn25Ga25−xFex (x=1–6) microwires were investigated. The unique solidification process during melt-extraction creates the micron-sized diameter wires with small grains and semicircular cross-section. At ambient temperature Ni50Mn25Ga25−xFex (x 5 are martensitic phases with seven-layered modulated (7M) structure. The results point out that martensite transformation temperatures are strongly related to Fe content due to the change of valence electron concentration (e/a). Reversible superelastic strains of 0.92% and 0.75% are obtained in Ni50Mn25Ga21Fe4 and Ni50Mn25Ga20Fe5 microwires, respectively. It is demonstrated that the temperature dependence of stress-induced martensite (SIM) stress follows the Clausius–Clapeyron relation. The temperature dependence of SIM stress in Fe-doped Ni–Mn–Ga microwires is 10.5 MPa/K.

High-quality Gd60Co15Al25 microwires with an average diameter of 40 µm were successfully fabricated by the melt-extraction method. The as-cast microwires undergo a second-order paramagnetic to ferromagnetic (PM–FM) transition at ∼100 K. Large values of the magnetic entropy change (−ΔSM ∼9.73 J kg−1 K−1) and the refrigerant capacity (RC ∼732 J kg−1) are achieved for a field change of 5 T. A careful analysis of critical exponents near the PM–FM transition indicates the significant effects of structural disorder on the long-range ferromagnetic interaction and the magnetocaloric response of the microwires. The excellent magnetocaloric properties make the Gd60Co15Al25 microwires very promising for use in magnetic refrigerators operating in the liquid nitrogen temperature range.

Ni50Mn25Ga25–xFex (1 ≤ x ≤ 6) microwires with a diameter of 30–50 µm were prepared by melt-extraction. The effects of Fe doping on the martensite transformation temperature, Curie point and magnetic properties before and after chemical ordering treatments were investigated. Experimental results show that Ni50Mn25Ga25–xFex microwires exhibit typical thermoelastic martensite transformation and magnetic transition. Transformation temperatures of the microwires increase with Fe content with a rate of 27.3 K/at%. Thermal hysteresis during martensite transformation is lowered after Fe doping. The Curie point of Ni50Mn25Ga25–xFex (1 ≤ x ≤ 6) microwires keeps stable at 390 K, which is 25 K higher compared with Ni2MnGa ternary alloy. After chemical ordering heat treatment, the microwires exhibit a typical ferromagnetic transition and a higher saturation magnetization at low field compared to as-extracted microwires.

Mitochondria are important for energy production and cardiomyocytes homeostasis. OMA1, a metalloendopeptidase, initiates the proteolytic process of pro-fusion protein, OPA1, to deteriorate mitochondrial structure and function. In this study, mouse embryonic fibroblasts (MEFs) and neonatal mouse cardiomyocytes (NMCMs) subjected to hypoxia-reperfusion (H/R) and/or H2O2 were used to mimic oxidative stress in the heart following ischemia-reperfusion (I/R). In vitro experiments demonstrated that H/R insult and H2O2 stimulation induced self-cleavage of OMA1 and subsequent conversion of OPA1 from long form to short form, leading to mitochondrial fragmentation, cytochrome c release, and apoptosis. By using Molecular Operating Environment (MOE) to simulate the binding interaction of 2295 phytochemicals against OMA1, epigallocatechin gallate (EGCG) and betanin were selected as candidates of OMA1 inhibitor. We found that EGCG directly interacted with OMA1 and potently inhibited self-cleavage of OMA1, leading to attenuated OPA1 cleavage. This study suggests that OMA1 inhibition induced by EGCG can serve as a potential approach to treat cardiac I/R injury.

Based on a comprehensive study of the effect of progressive DC Joule-heating annealing (DJA) on giant magneto-impedance (GMI) properties of melt-extracted amorphous microwires, we systematically analysed the different mechanisms for two types of GMI effect definition. Experimental results show that DJA can improve GMI response characteristics and magnetic field sensitivity (MFS) effectively for both definitions, but ΔZ/Z0 is enhanced much more than ΔZ/Zmax of the as-cast wires. At 20 MHz, the maximum GMI ratios, as denoted by ΔZ/Z0 and ΔZ/Zmax, of DJA microwires are enhanced to 582.59% and 639.13%, while the values for the as-cast wires are 69.09% and 520.48% respectively. Meanwhile, the MFS (ξmax) and equivalent magnetic anisotropy field (Hk) increase to 1346.4%/Oe (ΔZ/Z0), 2927.9%/Oe (ΔZ/Zmax) and 1.1 Oe, respectively. These significant effects of GMI properties as denoted by Z0 are mainly attributed to the change of resistivity (ρdc) for amorphous microwires induced by DJA. Revealing the mechanism of different effects can also result in the development of a micromagnetic field sensor, especially for geomagnetic sensor applications (∼±1.0 Oe).

Main conclusion LARs promoted the biosynthesis of catechin monomers and inhibited their polymerization. The accumulation of catechin monomers and polymers was increased by up-regulating the expression of NtLAR and NtANR s in CsMYB5b transgenic tobacco. Tea is rich in polyphenolic compounds, and catechins are the major polyphenols in tea. The biosynthesis of polyphenols is closely related to the expression of the leucoanthocyanidin reductase (LAR) and anthocyanidin reductase (ANR) genes. In this paper, an evolutionary analysis and functional characterization of three CsLARs were performed. The phylogenetic tree showed that plant LARs could be grouped into three, including gymnosperms, monocotyledons and dicotyledons (clusters I and II). The eighth amino acid residue in a conserved LAR-specific motif is changeable due to a transversion (G → T) and transition (G → C) that occur in the corresponding codon. Therefore, plant LARs can be classified as G-type, A-type and S-type LARs due to this variable amino acid residue. Although (2R, 3S)-trans-flavan-3-ols were the products of recombinant CsLARs proteins expressed in Escherichia coli, both (2R, 3S)-trans and (2R, 3R)-cis-flavan-3-ols were detected in tobacco overexpressing CsLARs. However, a butanol/HCl hydrolysis assay indicated that overexpression of the CsLARs caused a decrease in polymerized catechins. A hybridization experiment with CsLARc + AtPAP1 also showed that no polymers other than epicatechin, catechin and glycoside were detected, although the accumulation of anthocyanins was markedly decreased. CsMYB5b promoted the biosynthesis of both flavan-3-ols and proanthocyanidins (PAs). Therefore, LARs promoted the biosynthesis of catechin monomers and inhibited their polymerization. The accumulation of catechin monomers and polymers was increased by up-regulating the expression of the NtLAR and NtANRs in CsMYB5b transgenic tobacco. Electronic supplementary material The online version of this article (doi:10.1007/s00425-017-2771-z) contains supplementary material, which is available to authorized users.

Understanding the relationship between the surface conditions and giant magneto-impedance (GMI) in Co-rich melt-extracted microwires is key to optimizing their magnetic responses for magnetic sensor applications. The surface magnetic domain structure (SMDS) parameters of ~45 μm diameter Co69.25Fe4.25Si13B13.5-xZrx (x = 0, 1, 2, 3) microwires, including the magnetic domain period (d) and surface roughness (Rq) as extracted from the magnetic force microscopy (MFM) images, have been correlated with GMI in the range 1–1000 MHz. It was found that substitution of B with 1 at. % Zr increased d of the base alloy from 729 to 740 nm while retaining Rq from ~1 nm to ~3 nm. A tremendous impact on the GMI ratio was found, increasing the ratio from ~360% to ~490% at an operating frequency of 40 MHz. Further substitution with Zr decreased the high frequency GMI ratio, which can be understood by the significant increase in surface roughness evident by force microscopy. This study demonstrates the application of the domain period and surface roughness found by force microscopy to the interpretation of the GMI in Co-rich microwires.

Phenylalanine ammonia-lyase (PAL), the branch point enzyme controlling the flow of primary metabolism into second metabolism, converts the L-phenylalanine (L-Phe) to yield cinnamic acid. Based on the sequencing data available from eight transcriptome projects, six PAL genes have been screened out, cloned, and designated as CsPALa - CsPALf. The phylogenetic tree showed that Cs PALs were divided into three subgroups, PALa and PALb, PALc and PALd, and PALe and PALf. All six Cs PALs exhibited indiscriminate cytosolic locations in epidermis cells and mesophyll cells. Then, the expression profiles of six PAL genes were qualitatively investigated and they displayed tissue-/induced-expression specificity in several tissues or under different exogenous treatments. Furthermore, in vitro enzymatic assays showed that all six recombinant proteins were characterized by the strict substrate specificity toward L-Phe, but no activity toward L-Tyr, and they displayed subtle differences in kinetics and enzymatic properties. These results indicate that CsPALs play both distinct and overlapping roles in plant growth and responses to environmental cues.

Herein, we report high magnetocaloric performance of melt-extracted metallic glass Gd 60 Al 20 Co 20 microwires, which exhibit a large and reversible magnetocaloric effect (MCE). The isothermal magnetic entropy change (−Δ S m ) reaches as high as 10.1 J kg −1 K −1 and the refrigerant capacity (RC) has a large value of 681 J kg −1 for a field change of 5 T. The as-obtained Gd-based metallic glass microwires hold a great promise for multifunctional applications in MCE-based refrigeration of liquid nitrogen temperature range.

We reported the magnetocaloric properties of Heusler-type Ni48Mn26Ga19.5Fe6.5 microwires with diameter of ∼50 μm which were fabricated by a precise melt-extraction method. The Fe-doped Ni–Mn–Ga microwires after chemical ordering heat-treatment exhibit negligible thermal and magnetic hysteresis along the axial direction due to their small magnetocrystalline anisotropy and display excellent magnetocaloric effect (MCE) for both magnetic (paramagnetic–ferromagnetic) phase transition and structural (austenite–martensite) phase transition. The maximum entropy change (−ΔSm), ∼4.7 J kg−1 K−1, is obtained during the structural transition induced by an external magnetic field of 50 kOe at a temperature of ∼361 K. Moreover, tiny positive magnetic entropy also appears when the applied field is lower than 5 kOe.

Coaxially dielectric samples consisting of different packing ratios of glass-covered Fe73.5Si13.5B9Nb3Cu1 amorphous wires embedded in a paraffin wax matrix were fabricated, and the influence of short-wire packing ratio (3%–9% in mass fraction) and thickness (1–7 mm) on the microwave absorption properties was systematically investigated in microwave frequency range of 2–18 GHz. X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and scalar network analyzer (SNA) were used for characterizing microstructure and evaluating microwave absorption properties. Experimental results show the significant frequency (6–18 GHz) dependence of the complex relative permeability and permittivity. The reflection loss (RL) with different thickness and short-wire packing ratio reveals that the composite sample containing 7% exhibits better microwave absorption behavior with its minimum value of RL reaching −34 dB in thickness of 3 mm at 14 GHz. Therefore, it is significantly useful to develop microwire-dielectric materials with much wider absorption band for microwave absorption applications.

We report rapidly quenched Gd-based metallic glass micro-fibers with a nominal composition of Gd 55 Al 25 Co 20 , which are fabricated by melt-extraction method, and possess remarkable magnetic properties and excellent mechanical performances. Attractively, these metallic glass micro-fibers exhibit a noticeable and reversible magnetocaloric effect (MCE). For a magnetic field change of 5 T, the isothermal magnetic entropy change (−Δ S m ) reaches as high as 9.7 J kg − 1 K − 1 and the refrigerant capacity (RC) achieves a relatively large value of 652 J kg − 1 . In addition, the Arrott plots indicate that the ferromagnetic-paramagnetic transition is of second-order. Remarkably, the average value of maximum tensile strength for Gd 55 Al 25 Co 20 metallic glass micro-fibers is statistically calculated to be 1189 MPa and their fracture reliabilities were characterized using Weibull and lognormal methods, respectively. It is demonstrated that the as-extracted metallic glass micro-fibers have an excellent fracture modulus of 19.9 and a high security threshold of 796 MPa for practical application. Though with a low Curie temperature, the adaptability and outstanding characteristics of the melt-extracted Gd-based metallic glass micro-fibers are expected to be applied in the multifunctional fields of MCE-based refrigeration.

We report a systematic study of a new class of melt-extracted Ni49.7Mn25.0Ga19.8Fe5.5 polycrystalline microwires in terms of fabrication, microstructural characterization, and evaluation of shape memory effects (SMEs). The as-extracted microwire has enhanced ductility due to its fine grains with diameters of 1–3 µm. The total strain in its martensite state reached 2.14% as loading at 350 MPa and 100% plastic deformation strain recovery was achieved after heating process. During thermo-cycling tests, a fully recoverable transformation strain of 1.5% was obtained under a tensile bias-stress of 468 MPa. It can be therefore concluded that Fe-doped microwires display the least strain dependence on stress compared with other alloys such as NiTi and NiMnGa, and could be useful in devices required constant stress output.

Co68.15Fe4.35Si12.25B15.25 (at%) amorphous microwires with a smooth surface and a circular cross-section were fabricated by the glass-coated melt spinning method. Their mechanical properties were evaluated through tensile tests of the glass-coated amorphous microwires, and their fracture reliability was estimated using two- and three-parameter Weibull analysis. X-ray diffraction and transmission electron microscopy results showed that these glass-coated Co-based microwires were mostly amorphous. The coated Co-based microwires exhibit a tensile strength of 1145 to 2457 MPa, with a mean value of 1727 MPa and a variance of 445 MPa. Weibull statistical analysis showed that the tensile two-parameter Weibull modulus of the amorphous microwires is 4.16 and the three-parameter Weibull modulus is 1.61 with a threshold value as high as 942 MPa. These results indicate that the fabricated microwires exhibit good tensile properties and fracture reliability, and thus appear to be good candidates for electronics reliability engineering applications.

In this work, we report a comprehensive investigation on mechanical and giant magneto-impedance (GMI) properties of melt-extracted Co-rich amorphous microwires with the nominal composition of Co69.25Fe4.25Si13B13.5−xNbx (x = 0, 1, 2, 3, 4). Results show that the tensile strength and GMI properties gradually increase with the substitution of B by Nb at first, and then decrease with a further Nb substitution. The melt-extracted microwires with the substitution of B by 3% Nb exhibit a maximum tensile strength σm of 4000 ± 50 MPa owing to the formation of nanosized crystals in the amorphous matrix. In addition, the substitution of B by 1% Nb assures an excellent GMI property. At 5 MHz, the maximum GMI ratio [ΔZ/Zmax]max for the melt-extracted microwires reaches as high as 450 ± 10% versus 380 ± 10% for traditional CoFeSiB microwires and the field-response sensitivity increases from 350 ± 10% Oe−1 to 700 ± 10% Oe−1 for 1% Nb substitution. It is thus concluded that both mechanical and GMI properties of the melt-extracted Co-based amorphous microwires can be greatly improved by properly adding Nb, and this is promising for many engineering applications, including high-resolution magnetic, stress and biomedical sensors.

We report here on a comprehensive study of an alternating-current Joule annealing (ACJA) method for optimizing the giant magnetoimpedance (GMI) effect of Co-rich amorphous wires for sensor applications. Experimental results indicated that the proper ACJA treatment can drastically improve the GMI property of as-cast wire. At 10 MHz, the maximum GMI ratio [ΔZ/Z0]max of ACJA-ed wire increase to 205.38%, which is nearly 3.3 times that of 62.84% for as-cast wire, and the maxima field response sensitivity ξmax of ACJA-ed wire increases to 345.90%/Oe by more than twice that of 170.92%/Oe for as-cast wire. With an increase of AC amplitude, a remarkable dependence of GMI performance appears on the microstructural evolution such as the structural relaxation, the degree of local order, as well as circular magnetic domains. Importantly, the atomic order orientation incorporating HRTEM observation and circumferential permeability were effectively increased by the co-action of thermal activation energy and magnetic field energy during ACJA, further to enhance the magnetic properties to some extent. Based on both the numerical calculation of transient temperature rise and GMI behavior, we propose ACJA as an efficient annealing technique to achieve simultaneous best performance of [ΔZ/Z0]max and ξmax for potentially magnetic sensor applications in detecting weak magnetic fields.

Based on discrete element theory, a discrete element model was built to simulate the motion of single particle or particles, which provides some feasible and effective methods for determining the physical parameters and contact parameters of the discrete element model, and improves the authenticity and reliability of the material discrete element simulation. This paper provides some methods for obtaining physical parameters and mutual contact parameters. The shear modulus of limestone rock was obtained by uniaxial compression test. Using limestone raw material, the collision recovery coefficient was measured in a drop test using a high-speed camera and the static friction coefficient was obtained in a sliding plate test. The physical parameters and the contact parameters of the discrete element model of limestone were determined by measuring the stacking angle of limestone particles.

Giant magneto-impedance (GMI) is effectively enhanced by the mutual magnetic interaction between two amorphous microwires. A comparative study on GMI properties of a single wire and two wires arranged in parallel mode was reported in this work. Two-peak (TP) of impedance characteristic is presented when the dc external field changed from 0 to 320 A·m−1 in two-wire system, which is attributed to successive magnetization process in two wires induced by their magnetic interaction. And the evolution of single peak to TP phenomenon, when the distance between two wires is upto 8 mm, evidences a distance dependence of transformation from successive magnetization to simultaneous via a corresponding distance dependence of magnetostatic interactions. It is proposed that the recombination of magnetic interaction and the shielding effect results in a distance dependency of GMI response. When the distance is 8 mm, the magnetization process is close to synchronous between two wires, which give rises to higher circular permeability and better GMI response. The impedance ratio ΔZ/Z increases from 74.5 % of single wire to 172.4 % at 10 MHz. However, when the distance is upto 12 mm, the magnetic interaction is weak and magnetization process is completely independent, and GMI response decreases, relatively. This indicates that the GMI response could be effectively improved in a two-wire connection with an optical distance, which is promising and useful for the application of high-performance GMI sensors.

We present systematic studies on the effect of Ni electro-plated wire-connecting technique on giant magneto-impedance (GMI) output stability of melt-extracted amorphous CoFeSiB microwires for potential sensor applications. The electro-plated microstructure was observed by scanning electron microscopy (SEM) and the GMI output stability was characterized by a precision impedance analyzer and a magnetically shielded space. Experimental results indicated that Ni electro-plating (at 4.0 A/dm2 for 230 s) caused the microwires to show homogeneous pyramid structures, better wettability and weldability, so improving the GMI output for reducing the RF wave emission and signal attenuation, minimizing the disturbance of stray capacity, and suppressing the destabilization and concussion at relatively high frequency, especially near RLC parallel resonance frequency, fp. Moreover, the wire-connecting by Ni electro-plating could enhance the GMI output stability under different applied magnetic fields and frequencies. It can therefore be concluded that the microwires with Ni electro-plated two-terminal are suitable as stable GMI sources of high-resolution magnetic sensors.