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Externalizing behavior and low academic performance present key developmental challenges for school-age children, with the potential for these domains to predict each other over time, leading to worsened outcomes. Yet, previous studies have yielded inconsistent conclusions about the directional pathways between externalizing behaviors and academic performance. Moreover, the moderating factors influencing these predictive pathways remain unclear. To clarify these relations, The current study conducted a meta-analysis on the longitudinal predictive relation between externalizing behaviors and academic performance, incorporating data from 124,695 students without clinically diagnosed behavioral problems or learning disabilities across 70 independent studies. The results revealed a bidirectional predictive relation between externalizing behaviors and academic performance, with comparable effect sizes for both the externalizing behavior to academic performance pathway (r = -.082, p <.001) and the reverse pathway (r = -.076, p <.001). Moderation analysis revealed that inattention-related behavior, shorter time intervals, and fewer white participants strengthen the predictive effect of externalizing behaviors on academic performance. In particular, as child age increases, the moderating effect of time interval is even stronger. For the academic performance leading to externalizing behavior pathway, inattention-related behavior, teacher-reported externalizing behavior, literacy-related performance, and GPA/grades were identified as factors contributing to an augmentation in the longitudinal predictive effect of academic performance on externalizing behaviors. Overall, the negative cycle between externalizing behavior and academic performance may be influenced by various factors, providing targeted recommendations for intervention and prevention. [ABSTRACT FROM AUTHOR]

Circular RNAs (circRNAs) have been progressively recognized as critical regulators in the pathology and pathophysiology of central nervous system disease. However, the potential role of circRNAs in intracerebral hemorrhage (ICH) is still largely unclear. Here, we demonstrate that circTrim37 expression was significantly upregulated at 3 days after ICH by circular RNA microarray and qPCR assays. Overexpression of circTrim37 could significantly ameliorate brain injury volume, brain edema, neurologic deficits, and inflammation in vivo after ICH. CircTrim37 promotes M2 polarization while restrains M1 polarization in vitro. Furthermore, circTrim37 acts as an endogenous sponge for miR-30c-5p, thereby inhibiting miR-30c-5p activity, leading to the upregulation of SOCS3 and making the balance of microglial response towards an M2 phenotype. Taken together, our results indicate the participation of circTrim37 and its coupling mechanism in ICH and provide a novel therapeutic target for ICH. [ABSTRACT FROM AUTHOR]

License plate recognition (LPR) is a crucial task in traffic management, but traditional methods face limitations in accuracy and speed that are mutually constraining. In this paper, we propose an efficient license plate recognition system that achieves high recognition accuracy while ensuring real-time recognition. In order to achieve high detection accuracy while minimizing computational effort in the license plate detection stage, we propose a lightweight cross stage partial dilated convolution (CSPDC) network. Firstly, we propose a lightweight downsampling design that reduces the computational effort of downsampling while retaining important feature information. Secondly, we introduce a lightweight feature extraction network that reduces computational effort and parameter count while maintaining the network's feature extraction capability. Finally, to prevent a decrease in detection performance after lightweight processing, we propose a cross stage partial dilated block that expands the receptive field of feature extraction to enhance the network's learning capability. Experimental results on the CCPD dataset demonstrate that our proposed system achieves a tradeoff between computational effort and accuracy, with an ACC of 99.3% and a detection speed of 89 FPS. We further deployed and tested our algorithm on the Huawei M6 tablet, and the test results shows the practical value of our proposed method. [ABSTRACT FROM AUTHOR]

The use of titanium implants as fixed supports following fractures in patients with OP can often result in sterile loosening and poor osseointegration. Oxidative stress has been shown to play a particularly important role in this process. While TSA has been reported to facilitate in vivo osteogenesis, the underlying mechanisms remain to be clarified. It also remains unclear whether TSA can improve the osseointegration of titanium implants. This study investigated whether TSA could enhance the osseointegration of titanium rods by activating AKT/Nrf2 pathway signaling, thereby suppressing oxidative stress. MC3T3-E1 cells treated with CCCP to induce oxidative stress served as an in vitro model, while an OVX-induced OP rat model was employed for in vivo analysis of titanium rod implantation. In vitro, TSA treatment of CCCP-treated MC3T3-E1 cells resulted in the upregulation of osteogenic proteins together with increased AKT, total Nrf2, nuclear Nrf2, HO-1, and NQO1 expression, enhanced mitochondrial functionality, and decreased oxidative damage. Notably, the PI3K/AKT inhibitor LY294002 reversed these effects. In vivo, TSA effectively enhanced the microstructural characteristics of distal femur trabecular bone, increased BMSCs mineralization capacity, promoted bone formation, and improved the binding of titanium implants to the surrounding tissue. Finally, our results showed that TSA could reverse oxidative stress-induced cell damage while promoting bone healing and improving titanium rods' osseointegration through AKT/Nrf2 pathway activation. [ABSTRACT FROM AUTHOR]

Background: Constitutive photomorphogenic protein 1 (COP1) plays a pivotal role in the development and progression of several human cancers and is reported to be upregulated in liver cancer. However, the role of COP1 in human liver cancer is unclear. Methods: We analyzed the COP1 expression in normal liver and liver cancer tissue samples using western blot and immunohistochemical analysis. We overexpressed and silenced COP1 in HepG2 and Huh7 cells and analyzed the effect on liver cancer cell proliferation. Additionally, COP1 was used as a bait to screen COP1-interacting proteins in a human cDNA library in a yeast two-hybrid screen and the results were confirmed with co-immunoprecipitation (co-IP) assays. Moreover, immunofluorescence staining was performed to assess co-localization. The protein levels of COP1 and mIL1RAcP were determined in clinical samples. Results: COP1 was upregulated in liver cancer samples compared to that in normal tissue samples. COP1 overexpression promoted proliferation of liver cancer cells, while COP1 knockdown exerted the opposite effect. Yeast two-hybrid screen identified interleukin-1 receptor accessory protein (IL1RAP) as a potential COP1-interacting protein. Co-IP assays further confirmed that COP1 interacts with both preIL1RAP and membrane-bound form of IL1RAP (mIL1RAP). Furthermore, COP1 upregulated mIL1RAP protein levels and promoted nuclear translocation and activation of the nuclear factor kappa B (NF-κB) (p50/p65) dimer. Additionally, we demonstrated that COP1 regulated mIL1RAP expression through K63-linked polyubiquitination, suggesting that COP1 plays a role in stabilizing mIL1RAP. Finally, the protein levels of COP1 and mIL1RAcP were found to be positively correlated in clinical samples. Conclusion: COP1 regulates IL1RAP, which in turn results in activation of the NF-κB signaling. Our findings suggest that the COP1/IL1RAP/NF-κB axis promotes proliferation of liver cancer cells and is a potential target for the treatment of liver cancer. [ABSTRACT FROM AUTHOR]

Intracerebral hemorrhage (ICH) is a lethal stroke with high mortality or disability. However, effective therapy for ICH damage is generally lacking. Previous investigations have suggested that lysosomal protein transmembrane 5 (LAPTM5) is involved in various pathological processes, including autophagy, apoptosis, and inflammation. In this study, we aimed to identify the expression and functions of LAPTM5 in collagenase-induced ICH mouse models and hemoglobin-induced cell models. We found that LAPTM5 was highly expressed in brain tissues around the hematoma, and double immunostaining studies showed that LAPTM5 was co-expressed with microglia cells, neurons, and astrocytes. Following ICH, the mice presented increased brain edema, blood-brain barrier permeability, and neurological deficits, while pathological symptoms were alleviated after the LAPTM5 knockdown. Adeno-associated virus 9-mediated downregulation of LAPTM5 also improves ICH-induced secondary cerebral damage, including neuronal degeneration, the polarization of M1-like microglia, and inflammatory cascades. Furthermore, LAPTM5 promoted activation of the nuclear factor kappa-B (NF-κB) pathway in response to neuroinflammation. Further investigations indicated that brain injury improved by LAPTM5 knockdown was further exacerbated after the overexpression of receptor-interacting protein kinase 1 (RIP1), which is revealed to trigger the NF-κB pathway. In vitro experiments demonstrated that LAPTM5 silencing inhibited hemoglobin-induced cell function and confirmed regulation between RIP1 and LAPTM5. In conclusion, the present study indicates that LAPTM5 may act as a positive regulator in the context of ICH by modulating the RIP1/NF-κB pathway. Thus, it may be a candidate gene for further study of molecular or therapeutic targets. [ABSTRACT FROM AUTHOR]

In order to obtain the strong Goss texture in the final product of Al–Cu–Mg alloy sheet, texture evolution and related mechanisms during solution treatment were investigated by macro- and micro-texture characterization techniques and new insights into Goss texture formation and development were obtained. The results show that the Goss texture formed from annealing recrystallization can further evolve into the stronger Goss texture during solution treatment. This Goss increment phenomenon attributes to the following two aspects. First, this is due to the recrystallized/substructured Goss grains growing into deformed Brass grains. In this case, the Σ9 boundary between Goss and Brass grains only shows the little mobility advantage during solution treatment. Thus, this mechanism is only part of reason for Goss increment, not a predominated one as it exists during annealing. Second, recrystallized Goss grain can slowly grow into substructured random grains, also partly leading to the increase of Goss texture. In addition, particles stimulated nucleation (PSN) effect on Goss texture formation and development was also revealed in details. It is suggested that the PSN effect by large Fe-rich phases restricts Goss grain nucleation and its subsequent growth, but is beneficial for the formation and subsequent growth of random-oriented nucleus. On the contrary, the PSN effect caused by relatively small θ and S phases won't hinder the development of Goss texture. [ABSTRACT FROM AUTHOR]

Chemical composition, surface morphology characteristics, and mineralogical characteristics of feed coals from six power plants were studied in this paper, as well as alteration behavior of mineral phase, functional groups, and trace elements during combustion. The apparent morphology of feed coals is different in compactness and order, while sharing a similar lamellar shape. Quartz, kaolinite, calcite, and illite are the main minerals in feed coals. There are obvious differences in the calorific value and temperature range in volatiles stages or coke combustion stages for feed coals. Peak positions for the main functional groups in feed coals are similar. After burning at 800 ℃, most organic functional groups in feed coals were lost in products, but the group of -CH2 on the side chain skeleton of n-alkane and the aromatic hydrocarbon bond (Ar–H) still existed in the ash, and the vibration of Si–O-Si bond and Al–OH bond in inorganic functional groups was strengthened. During combustion, Pb and Cr in feed coals will be accumulated in the mineral residues, unburned carbon, and residual ferromanganese minerals, along with the loss of organic matter and sulfide or the decomposition of carbonate. Pb and Cr are more easily adsorbed by the fine-graded coal combustion products. Occasionally, the abnormal phenomenon occurred in a medium-graded ash but with the maximum adsorption of Pb and Cr, which is mainly caused by the collision and agglomeration of the combustion products, or the adsorption capacity of different mineral components. The effects of diameter, coal species and feed coal on the forms of Pb and Cr in combustion products were also analyzed in this study. The study has some guiding significance for understanding the behavior track and alteration mechanism of Pb and Cr during coal combustion. [ABSTRACT FROM AUTHOR]

Wall slip is a microscopic phenomenon of cemented paste backfill (CPB) slurry near the pipe wall, which has an important influence on the form of slurry pipe transport flow and velocity distribution. Directly probing the wall slip characteristics using conventional experimental methods is difficult. Therefore, this paper established a noncontact experimental platform for monitoring the microscopic slip layer of CPB pipeline transport independently based on particle image velocimetry (PIV) and analyzed the effects of slurry temperature, pipe diameter, solid concentration, and slurry flow on the wall slip velocity of the CPB slurry, which refined the theory of the effect of wall slip characteristics on pipeline transport. The results showed that the CPB slurry had an extensive slip layer at the pipe wall with significant wall slip. High slurry temperature improved the degree of particle Brownian motion within the slurry and enhanced the wall slip effect. Increasing the pipe diameter was not conducive to the formation of the slurry slip layer and led to a transition in the CPB slurry flow pattern. The increase in the solid concentration raised the interlayer shear effect of CPB slurry flow and the slip velocity. The slip velocity value increased from 0.025 to 0.056 m·s−1 when the solid content improved from 55wt% to 65wt%. When slurry flow increased, the CPB slurry flocculation structure changed, which affected the slip velocity, and the best effect of slip layer resistance reduction was achieved when the transported flow rate was 1.01 m3·h−1. The results had important theoretical significance for improving the stability and economy of the CPB slurry in the pipeline. [ABSTRACT FROM AUTHOR]

Osteoarthritis (OA) is characterized by the progressive deterioration of articular cartilage, involving complicated cell-matrix interactions. Systematic investigations of dynamic cellular and matrix changes during OA progression are lacking. In this study, we use label-free two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) imaging to assess cellular and extracellular matrix features of murine articular cartilage during several time points at early stages of OA development following destabilization of medial meniscus surgery. We detect significant changes in the organization of collagen fibers and crosslink-associated fluorescence of the superficial zone as early as one week following surgery. Such changes become significant within the deeper transitional and radial zones at later time-points, highlighting the importance of high spatial resolution. Cellular metabolic changes exhibit a highly dynamic behavior, and indicate metabolic reprogramming from enhanced oxidative phosphorylation to enhanced glycolysis or fatty acid oxidation over the ten-week observation period. The optical metabolic and matrix changes detected within this mouse model are consistent with differences identified in excised human cartilage specimens from OA and healthy cartilage specimens. Thus, our studies reveal important cell-matrix interactions at the onset of OA that may enable improved understanding of OA development and identification of new potential treatment targets. Label-free two-photon excited fluorescence (TPEF) and second harmonic generation (SHG) imaging of osteoarthritic articular cartilage from patients and mice reveal the importance of cell-matrix interactions at disease onset. [ABSTRACT FROM AUTHOR]

In this work, effects of artificial aging temperature on the mechanical properties and precipitation behavior of a pre-strained Al–Cu–Mg–Ag alloy were investigated by hardness and tensile tests, and quantitative transmission electron microscope analysis. Three aging conditions, a single aging at a high temperature (T8H), a single aging at a low temperature (T8L) and an interrupted aging at low temperature following under-aging at a higher temperature (T8I4), were compared. Based on the quantitative analysis of the strengthening phases, the evolution law of the average diameter, thickness and volume fraction of Ω plates with the aging time for a pre-stretched Al–Cu–Mg–Ag alloy aged at 190 °C/160 °C may be predicted by the modified equations. The precipitation behavior of Ω precipitates was confirmed by considering the coarsening kinetics of them. Results show that a higher aging temperature can increase the precipitation kinetics of Ω phase and inhibit the precipitation of θ′ phase. Thus, a new type of interrupted aging treatment, T8I4 (3.2% pre-stretch + 190 °C/1 h + 160 °C/10 h), was proposed to enhance the strength of the pre-stretched Al–Cu–Mg–Ag alloy. [ABSTRACT FROM AUTHOR]

Texture growth and relative mechanism of Al–Cu–Mg–(Zr) alloy during annealing have been investigated by three dimensional Orientation Distribution Functions (ODFs), Electron Back Scattered Diffraction (EBSD) and Transmission Electron Microscopy (TEM). The results show that Zr addition in Al–Cu–Mg alloy restricts the preferable growth of recrystallized Goss grain, and fails to improve the total intensity of Goss texture. Recrystallized Goss is difficult to nucleate within Brass orientation even after full recrystallization, and Copper and S grains cannot preferably transform into Cube grains in Al–Cu–Mg–Zr alloy. Instead, the growth of random textures is favorable at the expense of deformed Brass, Copper and S textures. These phenomena can be well explained by relating to the disappearance of Σ5, Σ7 and Σ9 boundaries caused by Al3Zr pinning dislocation. In addition, it is found that the Brass texture of Al–Cu–Mg–Zr alloy can be enhanced at specific annealing temperature, which is attributed to the formation of recrystallized Brass grains. Lastly, the deformed Goss of Al–Cu–Mg–Zr alloy is energy-unstable as compared with Brass during annealing, and these deformed Goss grains will subsequently evolve into recrystallized Brass or random orientations. [ABSTRACT FROM AUTHOR]

Capillary penetration is widely existed in stope leaching, both the rate of liquid wetting ore and flow out of ore are affected by it. Stope leaching is carried out in a high-temperature environment when mining minerals with large burial depth. The mechanism of intra-particle liquid capillary penetration mechanisms at high-temperature have not been revealed. In this paper, samples with a size of Φ50 mm × 100 mm were selected for quantitative analysis. The capillary rise behaviour inside samples with different porosity were detected at 30 °C, 40 °C and 50 °C by using magnetic resonance imaging (MRI). In most cases, capillary rise height is underestimated when the outside wetting line is used as an indicator, because the rise height inside the sample is greater. The liquid capillary rise height increased slightly with the temperature, whereas the wetting surface profile remained unchanged. The capillary rise rate increased significantly with porosity, mainly due to the increase of internal effective porosity. The results help to understand the liquid penetration behaviour under high-temperature stope leaching condition, and lay a theoretical foundation for improving the liquid permeability. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of natural defect on the fatigue behavior of 5A06/7A05 dissimilar aluminum alloys welding joint, fatigue tests of two types of specimens with and without defects were carried out systematically under stress amplitude control conditions (stress ratio R=0.1) at normal temperature in laboratory air condition. Furthermore, a new parameter, i e, fatigue defect effect factor (FDEF) was introduced to assess the effect of defect on fatigue strength. The fatigue failure analysis was conducted as well to compare the fatigue and fracture behavior of the two types of specimens. The results show that: (1) natural defects have a strong effect on the fatigue lives of welding joint, and the differences between the specimens with and without defects can reach 80 times under a same theoretical net sectional stress; (2) the FDEF parameter introduced is effective to deal with the defect effect, and the FDEF decreases along with the increase of fatigue life. The mean relative error between the experimental data and predicted fatigue strength based on the FDEF is 10.2%; (3) the macro fracture of both types of specimens have three typical zones, i e, fatigue source zone, crack propagation zone and final fracture zone, while there are more than one fatigue sources for specimens with natural defects. The overall pattern of crack propagation zone and fracture zone are quite similar, but the morphologies are different in details. [ABSTRACT FROM AUTHOR]

The microstructures and mechanical properties of a hot extruded Al–Zn–Mg–Cu alloy pipe with variable cross-section are investigated by transmission electron microscopy, electron backscattering diffraction, hardness testing and finite element method. The results suggest that the variable temperature distribution at different positions along the extrusion direction after hot extrusion attribute to the changes in hot deformation degrees. The extruded profile at billet temperature of 410 °C and a ram speed of 1.5 mm/s shows a gradual increase in temperature from 416 to 467 °C at strains from 3.7 to 8.6 along the extrusion direction. The dynamic recovery (DRV) and partial dynamic recrystallization (DRX) are observed in the hot extruded profile, and high-angle grain boundaries fraction exponentially rises along the extrusion direction. The hardness at different positions of the hot extruded profile shows a nearly exponential decline along the extrusion direction, mainly ascribes to the decrease of the dislocation density that caused by the dynamic softening. [ABSTRACT FROM AUTHOR]

Natural rock is considered a solution for thermal energy storage (TES). comprehensive understanding of the effect of high temperature on the physical and mechanical properties of rock has an important effect on the carbon footprint. The novelties of this paper are as follows. First, the influence of high temperature on the distribution characteristics of sandstone pores is studied by defining four kinds of pores. Next, the spatial evolution of cross-scale pores is revealed. Then the average pore radius that can quantitatively represent the overall pore distribution is proposed. Finally, the influence of thermal treatment on the characteristic stress of sandstone is analyzed. An abnormal change in compactness and mechanical parameters is observed at 450 °C, and a reasonable explanation is provided. The results show that the most of physical and mechanical parameters have significant critical temperatures. In the range of 150–450 °C, the trend in small-scale pores, porosity, and average pore radius initially increases and then decreases. The mechanical parameters reach a maximum at 300 °C, and the mineral composition changes dramatically from 600 to 900 °C. The large-scale pores, porosity, and average pore radius increase, and the mechanical properties are weakened. These results are of great importance for the stability of the surrounding rock under high-temperature environments (industrial waste heat, nuclear waste disposal, and tunnel fires). [ABSTRACT FROM AUTHOR]

The dislocation slips during the hot- and cold-rolling processes, the texture evolution and the Goss-oriented grain refinement during the annealing of the Al–Cu–Mg alloy were investigated using optical microscope (OM), scanning electron microscope (SEM), electron back-scatter diffraction (EBSD), transmission electron microscope (TEM) and X-ray diffraction (XRD). Results shown that {111} <110> octahedral slip systems and {110} <111> non-octahedral slip systems can be activated during the hot- and cold-rolling. When the dislocation slips in {111} planes are suppressed, the cross-slip from the {111} planes to the {110} planes can be activated to coordinate deformation. The strain gradients between the adjacent grains of the alloy with the large cold rolling reduction during annealing are dramatically decreased by the strain homogenization, which suppresses the growth of {110} < 001 > Goss-oriented grains. The activation of {110} <111> slip systems may be led to the decrease of the intensity of {112} <111> Copper texture, and the effect of {110} <111> slip systems on the evolution of {001} < 100 > Cube texture is very small. With the increase of the cold rolling reduction and annealing temperature, the hardness of the annealed and rolled Al–Cu–Mg alloy all increases, strain hardening and grain refinement are responsible for the enhanced hardness. [ABSTRACT FROM AUTHOR]

Constitutive photomorphogenic 1 (COP1, also known as RFWD2), a ring-finger-type E3 ubiquitin ligase, has been reported to play a pivotal role in the regulation of cell growth, apoptosis, and DNA repair. Accumulating evidence has suggested that COP1 plays a role in tumorigenesis by triggering the ubiquitination and degradation of its substrates, but the potential mechanism remains unclear. In this study, COP1 was used as a bait in a yeast two-hybrid experiment to screen COP1-interacting proteins in a human brain cDNA library, and the results indicated that protocadherin 9 (PCDH9) was a potential binding protein of COP1. The interaction between and colocalization of COP1 and PCDH9 was further confirmed by coimmunoprecipitation (co-IP) assay and immunofluorescent staining. Subsequently, we demonstrated that COP1 acted as an E3 ligase to promote the ubiquitination and degradation of PCDH9 through the proteasome pathway in glioma cells. Furthermore, we identified that the type of COP1 mediated PCDH9 ubiquitination was Lys48-linked polyubiquitination. Finally, we found that the COP1 protein level was inversely correlated with the PCDH9 protein level in human glioma tissues. Taken together, our results suggest that COP1 is an E3 ubiquitin ligase for PCDH9 and reveal an important mechanism for PCDH9 regulation in human glioma. [ABSTRACT FROM AUTHOR]

Evolution of microstructure, texture, and hardness of the Al-Cu-Mg alloy was investigated by using scanning electron microscopy, electron backscatter diffraction, transmission electron microscopy, and x-ray diffraction. Results have shown that the hardness and Brass texture intensity of the Al-Cu-Mg alloy can be enhanced during the annealing process at 240-385 °C. The hardness enhancement of the alloy can be attributed to the fine-grain strengthening; the enhancement of the Brass texture intensity of the alloy is related to the polygonization of the deformed grains with Brass orientation. In addition, the evolution path of the Brass texture evolving into recrystallization texture during annealing can be summarized as follows: Brass texture → Goss texture → R-Goss texture → Cube texture. [ABSTRACT FROM AUTHOR]

The effect of solution treatments at high temperatures on the microstructure and fatigue performance of an Al-Cu-Mg alloy was investigated. Microstructural observation revealed that large secondary phases could be dissolved sufficiently by a strengthening solution at 507 °C for 20 min and shortening the solution time at the high temperature would bring about a significantly grain refinement. The fatigue test showed that the sample treated by the solution at the high temperature for a short time (507 °C/6 min) possessed the lowest fatigue crack propagation (FCP) rates. This was mainly attributed to the combined effect of the reduced large residual secondary phases and the conspicuous grain refinement. Reducing the large secondary phases remaining by the high temperature solution treatment was beneficial to limit the bridging of cracks, and refining the grains with Goss orientation could induce more crack deflection, consequently enhancing the fatigue resistance. [ABSTRACT FROM AUTHOR]

The localized corrosion behavior of Al-Cu and Al-Cu-Mg-Ag alloys was investigated in a naturally aerated 0.6 M NaCl solution by in situ observations and electrochemical techniques. The combined roles of Ag and Mg in affecting the corrosion resistance of Al-Cu alloys were observed using electron probe microanalysis and scanning Kelvin probe force microscopy. Results prove that Al-Cu-Mg-Ag alloy exhibits a weaker susceptibility to pitting attack than Al-Cu alloy. Such difference is ascribed to Ag and Mg atoms dissolved in Al matrix that increase the potential of the Al matrix, resulting in a smaller potential difference between the Al2Cu particles and Al matrix, that is, a weaker galvanic corrosion couple. [ABSTRACT FROM AUTHOR]

A bis-silane prepolymer-modified epoxy coating was applied to an Al-Zn-Mg-Cu alloy to improve corrosion protection. The bis-silane prepolymer was synthesized from tetraethoxysilane and γ-glycidoxypropyl trimethoxysilane. To study the mechanism of protection failure by the silane–epoxy hybrid coating and to determine an appropriate coating for protection, various coatings with different silane prepolymer contents were developed. The corrosion behavior of the coatings was studied by electrochemical impedance spectroscopy in a 3.5 wt.% NaCl solution. In comparison with silane monomer-modified epoxy coatings, the bis-silane-modified epoxy coating had lower coating capacitance (Cc), higher charge transfer resistance (Rdl) and lower double-layer capacitance (Cdl) during long immersion times, indicating a higher resistance to water permeation and stronger protection against substrate corrosion. The lowest Cc and Cdl values were obtained by mixing epoxy and the bis-silane prepolymer at a ratio of 1:1. [ABSTRACT FROM AUTHOR]

Evolution of Goss texture in an Al–Cu–Mg alloy during cold rolling was investigated by three-dimensional orientation distribution functions, electron back-scattered diffraction and transmission electron microscopy. The results showed that with increasing reduction from 23.7 to 80%, Goss textures gradually transformed into Brass texture through the activation of sole {111}<110> slip systems. When rolling reduction further increased from 80 to 86.3%, Goss texture rather than Brass started to rotate towards Copper and S components. The formation of Copper and S textures at these high reductions was attributed to the activation of {110}<110> and {001}<110> non-octahedral slip systems. [ABSTRACT FROM AUTHOR]

This paper presents an investigation on the influence of Mg content on the microstructures, tensile properties and three-point bending fatigue behavior of Al-Cu-Mg-Ag alloys. The results indicate that the alloy containing 0.70 wt.% Mg possesses lower tensile properties and higher fatigue performance compared to the one with 1.15 wt.% Mg. Increasing Mg content in Al-Cu-Mg-Ag alloys can enhance the nucleation and precipitation of Ω phase, as well as increase the volume fraction and number density of constituent particles. The investigation of the fatigue crack initiation and growth behavior of Al-Cu-Mg-Ag alloy using interrupted fatigue tests suggests that micro-cracks mainly nucleate on Al2Cu constituent particles and the fatigue life is mainly associated with the density of constituent particles. [ABSTRACT FROM AUTHOR]

A new four-stage aging treatment, which is composed of pre-aging, retrogression, natural aging (NA) and re-aging, is designed to increase the tensile properties and the fatigue life of forged 7050 aluminum alloy in this work. As compared to traditional T74 and RRA treatments, the four-stage aging-treated sample exhibits the highest tensile properties and ductility. The tensile strength and yield strength are 627 and 608 MPa, respectively, and the elongation is 11.3%. The results of TEM and DSC show that an increased G.P zones and fine η′ phase distributed in the matrix of the alloy are subjected by this new aging processing as compared with T74 and RRA treatments. The natural aging in four-stage aging treatment accelerates the diffusion of Mg vacancies, and promotes the precipitation of G.P zones in grain interior during re-aging stage. On the basis of dislocation shearing mechanism, more dense and fine G.P zones of four-stage aging temper result in the superior tensile strength as compared to T74 and RRA temper. In addition, a combination of shearable precipitates, fine GBPs and narrow PFZs is beneficial to the slip reversibility in the plastic zone at the crack tip, thereby reducing fatigue damage accumulation and increasing the fatigue life. [ABSTRACT FROM AUTHOR]

The texture evolution and fatigue crack propagation (FCP) of 2000 series alloys were investigated, respectively, by using scanning electron microscopy and x-ray diffraction. Results showed that the intensity change in different textures (such as Goss, Copper, S and Brass) abides by a linear evolution law, and a new model for texture evolution is proposed to predict the texture intensity during different heat treatments. With increasing annealing temperature, the FCP rate increased, but the damage tolerance decreased. The intensity of P texture was the key to affecting FCP rate and damage tolerance of the alloys. A new model based on the average grain diameter and P texture volume fraction was proposed to predict FCP rate and damage tolerance, and the predicted FCP rates agree very well with the experimental FCP rates of the alloys after different T83 treatments. [ABSTRACT FROM AUTHOR]

The effects of texture, including Brass, Goss + Cube and Cube, on the fatigue crack growth behavior in annealed Al-Cu-Mg alloy sheets were characterized in this investigation. Results showed that the Goss + Cube sheet possessed the greatest fatigue threshold value and the lowest fatigue crack propagation (FCP) rate, and the Brass sheet presented the smallest threshold value and the greatest FCP rate among the three textured sheets. SEM results showed more slip bands and more tortuous crack path formed in Goss + Cube sheet during cyclic loading, and EBSD results showed that numerous dramatic crack deflections occurred when fatigue crack propagated across Goss-grain boundary in Goss + Cube sheet, indicating that the grain orientations including Goss and Cube had positive effect on enhancing the FCP resistance. On the one hand, Goss and Cube grains have more high Schmid factor slip systems than Brass grain, promoting persistent slip bands formation and externally applied energy consumption, consequently giving rise to a high resistance to FCP. On the other hand, Goss grains could induce crack deflection with large twist angles, resulting in more energy consumption during the cracking process and thereby enhance the FCP resistance. [ABSTRACT FROM AUTHOR]

The fatigue property as well as stress corrosion cracking (SCC) resistance of an Al-Zn-Mg-Cu alloy thick plate in peak-aged and overaged tempers (T7351 and T7651) is systematically investigated by fatigue crack propagation (FCP) test and slow strain rate test (SSRT). Microstructural characterization is examined by transmission electron microscopy and scanning electron microscopy. Results reveal that the T7351 alloy has lower strength but higher electrical conductivity as compared to T7651 alloy. The FCP resistance of T7351 alloy is superior to that of the T7651 alloy due to the coarser precipitates in the highly overaged alloy in which the strain localization is reduced by promoting homogeneous slip. In addition, the SSRT test suggests a higher SCC resistance in T7351 alloy. The enhanced SCC resistance is found to depend on grain boundary precipitate characteristics and crack propagation resistance of the alloys. [ABSTRACT FROM AUTHOR]

The current understanding of texture evolution during deformation by rolling in aluminum alloys was summarized. This included understanding the evolution mechanisms and several key factors of initial texture, microstructure, alloy composition, deformation temperature, stress-strain condition, and rolling geometry. Related models on predicting texture evolution during rolling were also discussed. Finally, for this research field, the recommendations for controlling the formation of rolling textures were proposed. [ABSTRACT FROM AUTHOR]

The texture evolution in the intermediate (the 1/4 thickness) layer of hot-rolled Al-Cu-Mg alloy sheets was investigated by the x-ray diffraction technique, electron backscattered diffraction analysis and transmission electron microscopy observation. The results showed that a texture transition from the shear texture {001}<110> to the β-fiber textures occurred as the rolling temperature increased to 420 °C. The shear strain caused by friction resulted in this strong shear texture formation at the low rolling temperature. As the rolling temperature increased, the plane strain substituting the shear strain dominated in the intermediate layer, giving rise to a significant increase in the β-fiber textures. Increasing the rolling temperature was found to preferentially activate the non-octahedral {112}<110> slip system, thereby benefiting the development of strong Brass. At the low rolling reduction of 74%, the textures with low intensity tended to converge on the α-fiber, containing Goss, Brass, P and L components. As the rolling reduction increased to 90%, the textures were strengthened and gradually flew toward the β-fiber, containing Brass, Copper and S components. The S and Copper bands were found to be the preferential sites for the development of recrystallizing Cube grains during hot rolling. [ABSTRACT FROM AUTHOR]

The surface microhardness, as well as the fatigue crack propagation (FCP) resistance of 2524-T3 alloy, is improved by producing a 20-μm-thick amorphous electroless Ni-12% P coating on its surface. Compared to the substrate, this deposited EN coating possesses higher strength properties and exhibits a greater ability of accommodating the plastic deformation at the fatigue crack tip, thereby remarkably improving the FCP resistance in near-threshold and early Paris regimes. Regardless of the similar FCP rates in Paris regime (ΔK ≥ 16.2 MPa m0.5), the coated sample exhibits extended Paris regime and enhanced damage tolerance. [ABSTRACT FROM AUTHOR]

Texture and tempered condition combined effects on fatigue behavior in an Al-Cu-Li alloy have been investigated using tensile testing, cyclic loading testing, scanning electron microscope (SEM), transmission electron microscopy (TEM) and texture analysis. Results showed that in near-threshold region, T4-tempered samples possessed the lowest fatigue crack propagation (FCP) rate. In Paris regime, T4-tempered sample had similar FCP rate with T6-tempered sample. T83-tempered sample exhibited the greatest FCP rate among the three tempered conditions. 3% pre-stretching in T83-tempered sample resulted in a reducing intensity of Goss texture and facilitated T precipitation. SEM results showed that less crack deflection was observed in T83-tempered sample, as compared to other two tempered samples. It was the combined effects of a lower intensity of Goss texture and T precipitates retarding the reversible dislocation slipping in the plastic zone ahead the crack tip. [ABSTRACT FROM AUTHOR]

Enhanced heat resistance of Al-Cu-Mg alloy by employing a combined effect of pre-stretching and underaging has been characterized by thermal exposure, tensile testing, transmission electron microscopy (TEM) examination, and quantitative analysis. Tensile testing results showed that the samples subjected to both pre-stretching and underaging processing, presented a high tensile strength up to 440 MPa after thermal exposure at 200 °C for 500 h. This suggests that the long-time application temperature of Al-Cu-Mg alloys, which were normally applied at elevated temperature below 150 °C or even below 100 °C, can be raised to 200 °C by employing a combined effect of pre-stretching and underaging. TEM results showed that a fine and a narrow size distribution range of S′ phase was formed by the combined processing of pre-stretching and underaging, as compared to that without pre-stretching. Quantitative analysis results indicated that this narrow range of size distribution greatly reduced the growth rate of S′ phase during thermal exposure. It is suggested that this effect was ascribed to the Ostwald ripening mechanism. [ABSTRACT FROM AUTHOR]

The increases in the usage of nitrogen fertilizer result in deleterious impacts on the environment; thus, there is an urgent need to improve nitrogen use efficiency (NUE) in crops including rice ( Oryza sativa L.). Attentions have focused on quantitative trait loci (QTL) mapping of NUE-related traits using single experimental population, but to date, very few studies have taken advantage of association mapping to examine hundreds of lines for identifying potentially novel QTLs in rice. Here, we conducted association analysis on NUE-related traits using a population containing 184 varieties, which were genotyped with 157 genome-wide simple sequence repeat (SSR) markers. We detected eight statistically significant marker loci associating with NUE-related traits, of which two QTLs at RM5639 and RM3628 harbored known NUE-related genes GS1;2 and AspAt3, respectively. At a novel NUE-related locus RM5748, we developed Kompetitive Allele Specific PCR (KASP) single nucleotide polymorphism (SNP) markers and searched for putative NUE-related genes which are close to the associated SNP marker. Based on a transcriptional map of N stress responses constructed by our lab, we evaluated expressions of the NUE-related genes in this region and validated their effect on NUE. Meanwhile, we analyzed NUE-related alleles of the eight loci that could be utilized in marker-assisted selection. Moreover, we estimated breeding values of all the varieties through genomic prediction approach that could be beneficial for rice NUE enhancement. [ABSTRACT FROM AUTHOR]

Multi-step heat treatment effectively enhances the stress corrosion cracking (SCC) resistance but usually degrades the mechanical properties of Al-Zn-Mg-Cu alloys. With the aim to enhance SCC resistance as well as strength of Al-Zn-Mg-Cu alloys, we have optimized the process parameters during two-step aging of Al-6.1Zn-2.8Mg-1.9Cu alloy by Taguchi's L9 orthogonal array. In this work, analysis of variance (ANOVA) was performed to find out the significant heat treatment parameters. The slow strain rate testing combined with scanning electron microscope and transmission electron microscope was employed to study the SCC behaviors of Al-Zn-Mg-Cu alloy. Results showed that the contour map produced by ANOVA offered a reliable reference for selection of optimum heat treatment parameters. By using this method, a desired combination of mechanical performances and SCC resistance was obtained. [ABSTRACT FROM AUTHOR]

The refractive index resolution of a surface plasmon resonance (SPR) sensor has been significantly improved these years; however, higher sensing performance is always desired. In this work, we propose a line-monitoring, long-range SPR sensor whose resolution is much better than conventional SPR sensors. Also, in contrast to mono-channel detection, multichannel detection, using line-monitoring technique, can detect multiple channels concurrently. In this way, this system achieves a refractive index resolution of 4.0 × 10 refractive index units and can monitor multiple molecular interactions simultaneously. Finally, a model experiment detecting the Escherichia coli bacteria has demonstrated the potential for biomedical applications of this system. [ABSTRACT FROM AUTHOR]

The competitive grain growth in bicrystal samples during unidirectional solidification of a Ni-based superalloy was found to depend on secondary dendrites perpendicular to the grain boundary of bicrystal samples, rather than primary dendrites parallel to the thermal gradient as generally recognized. The primary dendrite orientation, however, had significance for the dendrite blocking in overgrowth processes and the resultant overgrowth rate during competitive grain growth. [ABSTRACT FROM AUTHOR]

In this study, the effects of thermal exposure at 200 °C on the mechanical properties and the growth of Ω plates in an Al-Cu-Mg-Ag alloy with high content of silver were investigated. It was shown that the tensile strength of the exposed alloy decreased with the increase of the mean lengths of Ω precipitates and the decrease in the volume fraction of the Ω phase. The decrease in tensile strength of the 165 °C/14-h-aged samples was less significant than that of 165 °C/2-h-aged samples because the lengthening rate of Ω plates was lower and the number density of Ω precipitates was higher in the 165 °C/14 h-aged samples. The thickening rate of Ω plates was very low during exposure at 200 °C because of high content of silver, and the growth behavior was caused mainly by the lengthening of Ω plates within the habit plane. High content of silver inhibited the thickening of Ω plates and promoted the lengthening of Ω precipitates during exposure. [ABSTRACT FROM AUTHOR]

We investigate the ability of a parallel scan spectral surface plasmon resonance imaging system in analyzing hybridization of single-stranded DNA (ssDNA) on microarray. The ssDNA probes are modified by a thiol group and thereby can be immobilized onto the gold film. Hybridization experiments are carried out by using both complementary and noncomplementary sequence to confirm the specificity of interaction. We also demonstrate that the data analysis is very important in reducing the noise and improving the resolution by comparing polynomial fitting method with the combination of polynomial fitting and centroid method. Finally, the results demonstrate that the parallel scan spectral surface plasmon resonance imaging system can be used for high-throughput analysis of the hybridization of the ssDNA. [ABSTRACT FROM AUTHOR]

The fatigue crack propagation behavior in the overaged Al-Zn-Mg-Cu alloy was characterized by optical microscopy, scanning electron microscopy, transmission electron microscopy and electron backscatter diffraction. The results revealed that a fatigue crack tended to transgranularly propagate in the near-threshold regime, whereas intergranular crack propagation was dominant at the high ΔK regime. The transition of crack propagation from a transgranular to an intergranular path that occurred in the Paris regime was strongly influenced by the misorientation of adjacent grains and precipitate free zones. In addition, a crystallographic model of crack propagation was proposed to interpret the transition. The fatigue short crack propagation on a single slip plane was responsible for the formation of a transgranular propagation path in the near-threshold regime. The fatigue long crack propagation, which was conducted by a duplex slip mechanism in the Paris regime, led to the formation of fatigue striations. The formation of a zigzag crack in the near-threshold regime was ascribed to the high misorientation of adjacent grains. [ABSTRACT FROM AUTHOR]

Mechanical properties and exfoliation corrosion behavior in Al-Cu-Mg alloy with various pre-strain percents were characterized in this study by means of hardness measurement, optical microscope, transmission electron microscope (TEM), x-ray diffraction (XRD), and electrochemical technique. The hardness of naturally aged alloy was significantly enhanced with increasing the pre-strain percents. The immersion tests and polarization measurements revealed that the pre-straining processing before natural aging reduced the resistance of the alloy to exfoliation corrosion (EXCO), which was mainly attributed to the increase of dislocations density and grain aspect ratio. The decrease of residual tensile stress may only play a minor role in the EXCO resistance. [ABSTRACT FROM AUTHOR]

The exfoliation corrosion (EXCO) behavior of Al-Zn-Mg-Cu-Cr alloy after severe cold rolling was investigated by optical microscope, transmission electron microscope, and electrochemical technique. The results show that the EXCO resistance decreased with increasing cold rolling reduction because of the grain boundaries which were decorated with the continuously distributed particles . After the solution treatment, the samples with different reductions retained the fibrous grains, and the elongated grains accelerated the growth of the corrosion cracks according to crack propagation analysis. Furthermore, the increase of deformation enhanced the degree of recrystallization, while the number of corrosion cells increased greatly when in the electrolyte, which tended to reduce the resistance to EXCO. [ABSTRACT FROM AUTHOR]

Microstructures and mechanical properties of an Al-Cu-Mg-Ag alloy aged for 1 h at temperatures in a range 25 °C to 450 °C were characterized in the present work by means of hardness tests, electrical conductivity measurements, and transmission electron microscopy (TEM). In-situ X-ray diffraction (XRD) was also employed to examine the precipitation behavior of Ω phase in a temperature range of 25 °C to 400 °C The in-situ Xray diffraction peak at 2θ = 26°-28° detected at elevated aging temperatures between 165 °C and 400 °C was attributed to the formation of Ω phase. TEM observations demonstrated the existence of Ω phase in the alloy when aged for 1 h at temperatures in a range 145 °C to 450 °C. [ABSTRACT FROM AUTHOR]

The existing form and grain refining effects of small zirconium addition in pure Mg, Mg-Yb and Mg-Zn binary alloys, and Mg-Zn-Yb ternary alloy (ZK60-Yb) were investigated. The results show that Zr element exists mainly in single and cluster particles of pure α-Zr or Zn-Zr compounds inside grains and at grain boundaries. Only the particles located in the interior of grains can act as the nucleus for α-Mg growth and effectively promote the formation of fine equiaxed grains. The broken and dispersed Zr-rich particles produced during the hot extrusion process can form nebulous banded structure in which these fine particles may act as obstacles to dislocation motion in wrought magnesium alloys. [ABSTRACT FROM AUTHOR]

The present work investigated the effects of additions with Sc and Er on the grain refinement in an Al-Cu-Mg-Ag alloy containing minor zirconium. The results indicated that 0.32 pct Sc addition interacted with 0.11 pct Zr and formed primary Al[sub3](Sc,Zr) phase. It acted as the nuclei for heterogeneous nucleation of a-Al grain growth in the melt and refined the grains greatly. Additions of 0.3 pct Er resulted in an Al[sub8]Cu[sub4]Er phase formed at the grain boundary and refined mainly the dendritic substructure. There is no visible interaction of Er and Zr. [ABSTRACT FROM AUTHOR]

Examines plasmids pG DNA RZ1 with green flourescent protein (GFP) reporter gene and a ribozyme gene incising penaeid white spot baculovirus, which were introduced into the fertilized eggs of Chinese shrimps. Materials and methods; Timing for gene transfer; Factors that affect GFP expression; Expression of GFP in various development stages.

Understanding the organization and mechanical function of the extracellular matrix (ECM) is critical for the development of therapeutic strategies that regulate wound healing following disease or injury. However, these relationships are challenging to elucidate during remodeling following myocardial infarction (MI) due to rapid changes in cellularity and an inability to characterize both ECM microstructure and function non-destructively. In this study, we overcome those challenges through whole organ decellularization and non-linear optical microscopy to directly relate the microstructure and mechanical properties of myocardial ECM. We non-destructively quantify collagen organization, content, and cross-linking within decellularized healthy and infarcted myocardium using second harmonic generation (SHG) and two photon excited autofluorescence. Tensile mechanical testing and compositional analysis reveal that the cumulative SHG intensity within each image volume and the average collagen autofluorescence are significantly correlated with collagen content and elastic modulus of the ECM, respectively. Compared to healthy ECM, infarcted tissues demonstrate a significant increase in collagen content and fiber alignment, and a decrease in cross-linking and elastic modulus. These findings indicate that cross-linking plays a key role in stiffness at the collagen fiber level following infarction, and highlight how this non-destructive approach to assessing remodeling can be used to understand ECM structure-function relationships. [ABSTRACT FROM AUTHOR]