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Reinforced concrete (RC) shear walls with precast steel-concrete composite modular (PSCCM) are strongly recommended in the structural design of nuclear power plants due to the need for a large number of process pipeline crossings and industrial construction. However, the effect of the PSCCM on the mechanical behavior of the whole RC shear wall is still unknown and has received little attention. In this study, three 1:3 scaled specimens, one traditional shear wall specimen (TW) and two shear wall specimens with the PSCCM (PW1, PW2), were designed and investigated under cyclic loadings. The failure mode, hysteretic curve, energy dissipation, stiffness and strength degradations were then comparatively investigated to reveal the effect of the PSCCM. Furthermore, numerical models of the RC shear wall with different PSCCM distributions were analyzed. The results show that the shear wall with the PSCCM has comparable mechanical properties with the traditional shear wall, which can be further improved by adding reinforced concrete constraints on both sides of the shear wall. The accumulated energy dissipation of the PW2 is higher than that of the TW and PW1 by 98.7 % and 60.0 %. The failure of the shear wall with the PSCCM is mainly concentrated in the reinforced concrete wall below the PSCCM, while the PSCCM maintains an elastic working state as a whole. Shear walls with the PSCCM arranged in the high stress zone will have a higher load-bearing capacity and lateral stiffness, but will suffer a higher risk of failure. The PSCCM in the low stress zone is always in an elastic working state.

In this paper, a high-entropy AlCoCrFeNi alloy were prepared using laser melting deposition (LMD) and the effect of heat treatment on their microstructure and corrosion resistance was studied. XRD, OM, SEM, EDS, EBSD and electrochemical tests were used to investigate the structure, microstructure, and corrosion resistance. The LMD and LMD-500 °C samples showed a single BCC phase structure. After the temperature was increased to 800 °C, a small amount of a Cr-rich and Fe-rich FCC phase and σphase precipitated at the grain boundaries, Al and Ni were enriched within the crystals. At 1100 °C, the σphase disappeared, and the FCC phase content increased from 1.4% to 5.2%. The average grain size was the largest at 500 °C, reaching 31.29 μm. In 3.5% NaCl solution, the LMD-500 °C sample showed a high self-corrosion potential and the lowest corrosion current density; the polarization resistance (Rp) and charge transfer resistance (Rct) were 5.266 × 105 Ω∙cm2and 1.248 × 108 Ω∙cm2, respectively, with the shallowest surface corrosion and the best corrosion resistance. In 0.5 mol/L NaOH solution, there were only a few corrosion holes in the samples before and after the heat treatment, and all the samples showed a good corrosion resistance. In 0.5 mol/L H2SO4solution, with the increase of temperature, the Cr, Al and other elements underwent intensified segregation. The corrosion resistance gradually improved, the Rpand the Rctwas 2.785 × 102 Ω∙cm2and 7.569 × 103 Ω∙cm2, respectively, at 1100 °C, providing the best corrosion resistance.

Hot-extrusion and cold-rolling were conducted on Mg–Ce binary alloys to explore the effect of cerium (Ce) on microstructure, texture and mechanical properties of Mg alloys. The addition of Ce results in significant grain refinement both in as-cast and hot-extruded samples. The basal texture is also weakened after extrusion and an inclined basal texture is formed with Ce addition. The strength and elongation of the Mg–Ce alloys are improved simultaneously due to such grain refinement and texture weakening effect. After cold-rolling, plenty of twins are found in the pure Mg and AZ31 plates while grains in the Mg-0.3Ce plate deform more uniformly without lamellar twin structure. Furthermore, Mg-0.3Ce alloys own strong and continuous strain hardening because Ce atoms and Mg–Ce precipitated phases serve as obstacles for dislocation slip.

Herein, six types of Al–7Si–xCu–0.35Mg–0.12Ti–0.24Zr–0.05Sr alloys were prepared with different Cu contents (x= 0, 1.8, 2.1, 2.4, 2.7, and 3.0). The effects of Cu addition and spheroidization treatment on the microstructure and mechanical properties of the alloys were examined. The findings demonstrated that the θ-Al2Cu phase tended to concentrate near the β-Al5FeSi phase. Furthermore, Cu could refine the grain and passivate the eutectic Si. Among the as-cast alloys, the mechanical properties were found to be optimal when the Cu content was 2.7 wt%, with ultimate tensile strength (UTS), yield strength (YS), and elongation (El) values measuring 251.1 MPa, 159.5 MPa, and 5.7%, respectively. Despite the decrease in El, the UTS and YS improved by 23.6% and 23.5%, respectively, compared to the C0 alloy. However, excessive Cu content aggregated and adhered to the massive θ-Al2Cu phases, weakening the mechanical characteristics of the alloy. In addition, the spheroidization treatment caused significant spheroidization in the eutectic Si and promoted a more uniform size distribution. This treatment also facilitated the transition of the solid solution of numerous θ-Al2Cu phase into a matrix, leading to a uniformly dispersed precipitation of Al–Si–Cu and Al–Cu phases. Consequently, the mechanical properties of the alloys were considerably enhanced. When the Cu content was 2.7 wt%, the UTS, YS, and El of the alloy were 301.9 MPa, 174.4 MPa, and 9.1%, respectively, representing increases of 20.2%, 9.3%, and 59.7% compared with those of the as-cast alloy.

Zinc-modified hypoeutectic Al–Si–Cu–Mg–Cr–B alloy underwent a two-stage solution treatment at 520 °C for two hours and 550 °C for half an hour, followed by a two-stage aging treatment at 100 °C for three hours and 180 °C for eight hours. The impact of heat treatment and Zn addition on the eutectic Si phase, alloy compounds, and mechanical properties of the hypoeutectic Al–Si–Cu–Mg–Cr–B alloy was systematically investigated using an optical microscope, X-ray diffractometer, scanning electron microscope, energy spectrum analysis, and mechanical properties test. The findings revealed that heat treatment and Zn addition improved the size, morphology, quantity, and types of eutectic silicon phases and alloy compounds, as well as their mechanical properties. After heat treatment, the alloy displayed optimal characteristics with the addition of 0.3 wt% Zn. The eutectic Si phase of the alloy exhibited the most favorable morphology, the greatest variety of alloy compounds, the most favorable morphology and size, and the largest Q index, which is utilized to evaluate the overall tensile properties of the alloy. This indicates superior mechanical properties.

The addition of zinc (Zn) to a hypoeutectic Al–Si–Cu–Mg alloy leads to an improvement in grain size. It also causes a transformation of the needle-like structure of the β-Fe phase into a Chinese character-like or short rod-like α-Fe phase. Concurrently, the addition of Zn also improves the solidification temperature range of the alloy and enhances the fluidity of the alloy. The alloy exhibits the most optimal microstructure and the narrowest solidification temperature range when 0.3 wt% of Zn is added. The results demonstrate that the alloy's fluidity is enhanced by 91.55% compared to the traditional unmodified Al–8Si–1Cu–0.35 Mg casting alloy. Furthermore, the addition of 0.3 wt% Zn resulted in a maximum value of 281.5 MPa for the mass index Q, indicating the optimal tensile properties.

The AZ31 magnesium alloy with different grain sizes was prepared by adjusting the heat treatment process, and then the tension and compression tests were carried out to explore the effect of grain sizes and loading conditions on the microstructures and properties of the magnesium alloy. The Hall-Petch slope presented dramatic anisotropy under tension (181 Mpa· μm1∕2) and compression (115 Mpa· μm1∕2), the geometric compatibility factor (m′) and the difference in activation stress between the initiated deformation modes of two neighboring grains (σd) were calculated to analyze the anisotropy quantitatively. In compression, it was found that the elongation increased with further grain coarsening, which was attributed to the fact that more twins were initiated in the coarse grains and the preferred initiation of twinning to inhibit competitive crack initiation.

In this study, Al–Si matrix composites containing different contents of in situ TiB2particles and (Ce+Yb) were fabricated via a mixed salt–metal reaction of KBF4and K2TiF6and the effects of the reinforcement particles on the microstructure and mechanical properties of the composites were investigated. Results revealed that the addition of TiB2particles and (Ce+Yb) further refined the α-Al grains and modified the eutectic Si phase of the composite. Moreover, the combined addition of (Ce+Yb) resulted in the suppression of TiB2agglomeration, causing a notable modification in the distribution and morphology of TiB2particles as well as a significant reduction in their size compared with the condition without the addition of (Ce+Yb). The mechanical properties of 3 wt.% TiB2/Al–Si matrix composites with the combined addition of 0.4 wt.% (Ce+Yb) reached the maximum values with the ultimate tensile strength, yield strength, and elongation of 372.4 MPa, 268.7 MPa, and 4.5%, respectively, which increased by 30.1%, 40.1%, and 9.8%, respectively, compared with those of Al–Si matrix alloy. Optical microscopy, scanning electron microscopy with energy-dispersive spectroscopy, and X-ray diffraction were used to demonstrate the presence of (Ce+Yb)-containing precipitates, other precipitates, and in situ TiB2particles.

Polybrominated dibenzofurans (PBDFs) are characteristic dioxin-like products of polybrominated diphenyl ether (PBDE) photolysis. In this study, competition mechanisms of radical-based cyclization and hydrogen abstraction reactions are proposed in PBDF formation. Commonly, the orthoC–Br bond dissociation during photolysis generates aryl radicals, which undergo intramolecular cyclization to form PBDFs or hydrogen abstraction with hydrogen donors (such as organic solvents and water) to form lower brominated PBDEs. By using 2,4,4′-tribromodiphenyl ether (BDE-28) as the model reactant, the experimental PBDF formation ratios in various solutions are explained quantitatively by the calculated rate constants of cyclization and hydrogen abstraction reactions using the density functional theory (DFT) method. The solvent effect of pure and mixed solvents on PBDF formation is illustrated successfully. The structure-related hydrogen donation ability for hydrogen abstraction controls the bias of competition reactions and influences PBDF formation. Water resulted to be the most significant generation of PBDFs. Fulvic and humic acid display higher hydrogen donation ability than small-molecule organics due to the partitioning effect in aqueous solution. Quantitative structure–activity relationship (QSAR) models of the calculated rate constants for 512 cyclization and 319 hydrogen abstraction reactions using 189 PBDEs as the initial reactants in water are established, revealing the high risk of PBDF formation in aqueous solution.

In the present work, the in situ TiB2particle-reinforced Al–Si matrix composites with or without (Ce + Yb) were fabricated by mixed salt–metal reaction, and the effect of TiB2and (Ce + Yb) on microstructure and mechanical properties were investigated. The results showed that the combined addition of 0.4 wt% (Ce + Yb) and 3 wt% TiB2further facilitated the uniform microstructure and modified the eutectic Si of composites. Meanwhile, the combined addition of (Ce + Yb) promoted the nucleation and inhibited the growth of TiB2particles. The mechanical properties of the composites with 0.4 wt% (Ce + Yb) and 3 wt% TiB2reached maximum values with ultimate tensile strength, yield strength and elongation of 240.5 MPa, 169.8 MPa and 6.6%, which were 53.8%, 116.1% and 164.0% higher compared to the Al–Si matrix alloy. The fractography observations indicated that the fracture mode of the composites belongs to a typical of mixed brittle–ductile fracture. But the combined addition of (Ce + Yb) is beneficial to improve the plasticity of the composites.

An Al–8Si–1Cu–0.35Mg casting alloy with (Mn + B) composite addition was prepared via traditional ingot metallurgy. The effects of (Mn + B) composite addition on the α-Al dendrites, AlB2phase, Fe-rich phase, fluidity, and mechanical properties of the hypoeutectic Al–8Si–1Cu–0.35Mg casting alloy were systematically studied via optical microscopy, scanning electron microscopy, energy–dispersive spectroscopy analysis, and fluidity and mechanical property tests. Results show that (Mn + B) addition refines the α-Al dendrites. The α-Al phase and AlB2particles function as heterogeneous nucleation particles to promote alloy nucleation, and the coarse dendrites are transformed into fine equiaxed crystals. The best effect is observed when 0.6 wt% Mn and 0.1 wt% B are added. (Mn + B) composite addition improves the morphology of the Fe-rich phase in the alloy and transforms the needle-like β-Fe phase into a dendritic Fe-rich phase and α-Fe phase. Furthermore, the grain refinement of the alloy and the improvement of the Fe-rich phase enhance the fluidity of the alloy. When 0.6 wt% Mn and 0.3 wt% B are added, the fluidity is the best, which is 77.5% higher than that without addition. (Mn + B) composite addition has minimal effect on the hardness of the alloy. The best mechanical properties are obtained upon the addition of 0.6 wt% Mn and 0.2 wt% B. In particular, the tensile strength and elongation are 235 MPa and 8.6%, respectively. These values are 40.1% and 100% higher than those obtained without addition, respectively. The fracture mode of the alloy also changes from ductile–brittle mixed fracture to ductile fracture.

DNA methylation is a conserved epigenetic modification with a critical role in regulating gene expression and maintaining genomic stability. Methyl-CpG-binding protein 4 (MBD4) binds to the methylated sequences and regulates gene expression. The Pearl oyster Pinctada fucata martensiiis a commercial oyster species used for cultivating seawater pearls in China. To clarify the function of MBD4 from P. f. martensii(PmMBD4), we obtained the regulatory genes of PmMBD4 by DNA affinity purification sequencing (DAP-seq) and RNA interference (RNAi) techniques and analyzed the binding ability of PmMBD4 to methylated DNA sequences. The results of subcellular localization analysis showed that PmMBD4 was present in both nucleus and cytoplasm. The combined analysis of DAP-seq and whole genome bisulfite sequencing revealed that all the binding fragments of PmMBD4 were methylated. The downregulated expression of PmMBD4 by RNAi decreased the enzyme activities of superoxide dismutase, catalase, and inducible nitric oxide synthase. The combined analysis of DAP-seq and transcriptome showed that PmMBD4 inhibited the immune response through the Lysosome and other signaling pathways. These results indicate that PmMBD4 is involved in regulating the immune response in pearl oysters by binding to methylated DNA sequences.

In this study, Al-6Si-0.6Mg-0.6Cu-0.2Cr alloys were prepared with the combined addition of (Ce+Yb) using the traditional ingot metallurgy method. The synergistic effects of (Ce+Yb) modification on the microstructure, including α-Al dendrites and eutectic Si phases, as well as the mechanical properties of Al-6Si-0.6Mg-0.6Cu-0.2Cr cast alloys were systematically investigated using differential scanning calorimetry (DSC), optical microscopy (OM), scanning electron microscopy (SEM), energy diffraction spectrum (EDS), X-ray diffraction (XRD), transmission electron microscopy (TEM) and mechanical tests. The results showed that the combined addition of (Ce+Yb) refined the α-Al grains and modified eutectic Si phases, with the combined addition of 0.6 wt% (Ce+Yb) exhibiting the best impacts on them. The Al11Ce3and Al3Yb intermetallics were also obtained from the modification. Moreover, the Al11Ce3and Al3Yb intermetallics functioned as strengthening precipitates and the eutectic Si phases were further spheroidized in the alloy during heat-treatment processing with the combined addition of (Ce+Yb). Coupled with heat treatment, the alloy with 0.6 wt% (Ce+Yb) exhibited enhanced mechanical properties with microhardness, ultimate tensile strength, yield strength and elongation of 89.4%, 114.1%, 183.9% and 208.0%, respectively, which were higher than those of the alloy without (Ce+Yb) modification and heat treatment. Notably, when the alloy was modified with the combined addition of (Ce+Yb), its strength significantly improved, whereas the elongation was not reduced and inversely was increased.

By varying the tempering temperature, the effects of various tempering temperatures on the microstructure and properties of the coating were investigated. The results show that after heat treatment, eutectic carbides of the original coating disappear and spherical granular carbides resurface. The form and size of alloy carbide alter as the tempering temperature changes. The alloy carbide microstructure size is more rounded when the tempering temperature is 500 °C, and the average hardness is 658 HV, which is 4.9% greater than the original coating. The wear loss is least at a tempering temperature of 500 °C. The abrasion loss is 0.46 and 0.76 times that of the original coating when the load is 50 N and 75 N, respectively. The corrosion current density after tempering at 700 °C is the lowest in the electrochemical experiment, but the self-corrosion potential is the largest.

Objectives:This study aims to investigate the efficacy and safety of local lauromacrogol injection in the treatment of hypopharyngeal hemangioma. Methods:From Aug 2015 to May 2021, 13 consecutive patients suffering from hypopharyngeal hemangioma underwent local lauromacrogol injection assisted by endoscope in this prospective clinical series. All patients were followed up regularly and the therapeutic effects and complications were observed. Results:A total 13 of patients were enrolled, including 11 men and 2 women, with an average age of 48.5 years (range 25–76 years). The sizes of the hemangioma ranged from 0.5 × 1.0 cm to 3.5 × 3.5 cm. After 1 to 40 months of follow-up, 12 patients were cured and 1 was significantly effective after 1 to 4 (mean 1.8) injections. All patients suffered varying degrees of postoperative pain or foreign body sensation. 3 patients were significantly affected by local swelling of the injection site, 2 of which underwent prophylactic tracheostomy postoperatively and 1 patient returned to the ward with endotracheal intubation postoperatively. No complications such as mucosal ulceration, fever, and allergies occurred. Conclusions:Lauromacrogol injection is a safe and effective method to treat hypopharyngeal hemangioma.

Texas electricity market saw a recent integration of electricity transmission as a part of Competitive Renewable Energy Zones (CREZ). Exploiting the commissioning date of CREZ based transmission integration as an exogenous shock, we analyze the effect of transmission expansion on market clearing prices of Congestion Revenue Rights (CRR). Reduced form estimates suggest that excess transmission led to a lowering of CRR prices for contracts at all Times of Use. We find strong evidence of spatial, distributional, and firm specific heterogeneity. The paper shows that transmission expansion enhanced efficiency of the CRR market in terms of a spatial convergence in prices and a decrease in aggregate auction expenditure of approximately $260 million over a period of 4.5 years post CREZ.

In Inconel 783 alloy, there are mainly two kinds of strengthening phases of β and γ’. In addition, it is found that there are other precipitated phases in the alloy’s β phase. By means of multiple testing methods, the types and functions of the precipitated phase in the β phase were determined. The results showed that the precipitated phases from β phase were nanoscale Nb and Ti carbides and a large number of white needle-like Laves phases. The former, due to its small size, which can improve the grain boundary slip resistance of the alloy, thus improves the shaping of the material. While the latter, due to its sharp shape and due to its large amount, destroys the original structure of the β phase and greatly reduces the room temperature plasticity of the alloy.

In this paper, the removal of the sulfide layer formed on an FV(520)B stainless steel in the simulated environment of air compressor blade service conditions in a reaction kettle by arc plasma was investigated to explore the mechanism and technology of the sulfide layer removed by arc plasma from a blade surface. The sulfide lattice energy is studied by using the Born Haber cycle. Besides, the energy balance of the removal process is calculated. The treated surface morphology of samples was analyzed by scanning electron microscopy and energy dispersive spectrometer. The results indicate that the energy of the arc spot is enough to evaporate the sulfide film. Due to the different electronic work functions, an arc spot is first formed on the sulfide film, and then the voltage signal is segmented during the removal process. The voltage signal in the removal process can remove sulfide without harming the metal matrix. Besides, the increase in current can improve the removal efficiency and the surface roughness of the sample. It can be revealed, by analyzing the surface composition of samples with different currents, that the sulfur content is very low, indicating that it is feasible to remove the sulfide layer by arc spot plasma.

In cross-language question retrieval (CLQR), users employ a new question in one language to search the community question answering (CQA) archives for similar questions in another language. In addition to the ranking problem in monolingual question retrieval, one needs to bridge the language gap in CLQR. The existing adversarial models for cross-language learning normally rely on a single adversarial component. Since natural languages consist of units of different abstract levels, we argue that crossing the language gap adaptatively on different levels with multiple adversarial components should lead to smoother text representation and better CLQR performance. To this end, we first encode questions into multi-layer representations of different abstract levels with a CNN based model which enhances conventional models with diverse kernel shapes and the corresponding pooling strategy so as to capture different aspects of a text segment. We then impose a set of adversarial components on different layers of question representation so as to decide the appropriate abstract levels and their role in performing cross-language mapping. Experimental results on two real-world datasets demonstrate that our model outperforms state-of-the-art models for CLQR, which is on par with the strong machine translation baselines and most monolingual baselines. [ABSTRACT FROM AUTHOR]

A large number of strip-like structures were found distributed along the axial direction of inconel 783 alloy bolts. Large-sized Nb were concentrated and precipitated in the interior, which makes the material structure uneven, resulting in a reduction of toughness and plasticity. Adopting a heat treatment method for increasing the solution temperature and at the same time prolonging the aging time improved the material properties to a certain extent. The results show that the large Nb easily develops inclusions, which reduces the impact properties of the material. After heat treatment, the strip-like structures disappeared, the size of the Nb decreased and nano-scale carbides were precipitated out, thus increasing plasticity by 11.5 %, toughness by nearly two times and improving the comprehensive mechanical properties in general.

Low-silica pellet is beneficial for blast furnace to reduce the amount of slag and fuel rate. However, the reduction swelling of low-silica pellet is serious. The effects of TiO2and MgO on such metallurgical properties as reduction swelling, reducibility and smelting performance of pellets have been studied and production of magnesium–titanium-bearing pellet with low silica is proposed in this paper. The MgO in sinter can be transferred to pellet and TiO2is provided by the pellet for blast furnace to protect hearth erosion. The magnesium–titanium-bearing pellet with low silica, in which the content of MgO is 1.7%, SiO2is 2.8% and TiO2is 1.2%, has been produced by the raw materials from Shougang Jingtang United Iron & Steel Co., Ltd. The pellets were used on 5500 m3blast furnace with a ratio of more than 28% stably and good technical and economical indexes were obtained. The average particle size of sinter was improved when the MgO content of pellet is increased without adding magnesium additives to sinter.

Internet of Electric Things (IoET) based on edge computing mode has advantages in functionality, communication efficiency and construction cost. However, the incompleteness of relevant security protocols restricts their application in smart grids. Therefore, we propose a lightweight three-layer device identity mutual authentication and key agreement protocol suitable for IoET with two-hops architecture. The simulation results of formal security analysis and automated security analysis toolset AVISPA on security attacks show that this protocol can meet the security requirements of identity authentication, device ID anti tracking, and session keys. Compared with recent lightweight third-party authentication protocols, our proposed scheme has advantages in resource consumption of servers and IoET Connector (IoetC) when multiple sensors require simultaneous authentication.

A new process for preparing fiber-reinforced silica sol shells for investment casting is proposed. The influence of fiber length on bending strength of shell is studied under the condition that fibers are not agglomerated or clustered. Polypropylene fibers were suspended under the action of air currents and adhered to the surface of shell with back-up slurry in the fiber placement device. Three millimeter and six millimeter lengths of fiber were used as reinforcing agents for the investment shell. The results showed that fibers could be placed uniformly on the surface of shell with slurry by air flowing in the fiber placement device, thereby enhancing the strength of the fiber-reinforced shell. Green bending strength of shell with additive of 6-mm-length fiber was higher than that of 3-mm-length fiber. This was due to the fact that the fibers were scattered into a reticular formation and the action of bridge connection between the longer fiber and matrix was stronger. Compared with the fiber of 3 mm length, the scanning electron microscope morphology of 6-mm-length fiber had typical characteristics on the fracture section of shell, which meant that fiber was pulled out from the shell with large mechanical force.

In this paper, Au/Fe3O4nanoparticles (Au/Fe3O4NPs) were prepared and a method for detecting malathion was constructed based on fluorescence resonance energy transfer (FRET) between Au/Fe3O4NPs and Rhodamine B (RhB). RhB could be electrostatically adsorbed to the surface of Au/Fe3O4NPs resulting in a low fluorescent background. The malathion hydrolysate with ‐SH can compete with RhB to form a stronger Au─S bond, thereby promoting the desorption of RhB from the surface of Au/Fe3O4NPs. This process causes the fluorescence emission to recover. The result demonstrated that fluorescence quenching efficiency of Au/Fe3O4could reach 50% at 579 nm and the fluorescence recovery efficiency of malathion hydrolysate could reach 61% at 579 nm. The limit of detection (LOD) of malathion was as low as 0.59 μM. The linear range of detection was 27.24–99.89 μM. Au/Fe3O4NPs could be reused by a magnetic concentration‐washing process. Schematic illutration for the detection of malathion based on FRET between the Au/Fe3O4NPs and RhB.

ABSTRACTGlycosaminoglycan (GAG), an important component of proteoglycan (PG), was biosynthesized with the initiation by peptide O-xylosyltransferase. O-xylosyltransferase activity was presented as a marker for increased PG synthesis. In the present study, a novel O-xylosyltransferase (OXT) gene was identified from Pinctada fucata martensii(PmOXT). The PmOXT-deduced protein sequence carried a typical water-soluble carbohydrate domain, branch domain, and xylosyltransferase domain. Homologous analysis of PmOXT presented the conserved DXD motif and catalytic structure characteristics. Phylogenetic tree analysis showed the traditional taxonomy and PmOXT clustered with Crassostrea gigas. PmOXTwas expressed in all the detected tissues and developmental stages. PmOXThad a significantly higher expression level in the shell formation associated tissues and developmental stages. PmOXTexpressed significantly decreased in the central zone of the mantle and marginal zone of the mantle after RNA interference; additionally, OXT activity and GAG content in the extrapallial fluid were significantly reduced compared with the control. Furthermore, the crystal tablets of prismatic layer displayed obvious holes and disordered crystals with obviously rough surface and irregular crystal tablets were observed in the nacre after RNAi. Results suggested that PmOXTaffected the shell formation by influencing the formation of GAGs in the process of addition to the core proteins.

AbstractMarine pearl production is directly influenced by the growth speed of Pinctada fucata martensii. However, the slow growth rate of this organism remains the main challenge in aquaculture production. Epidermal growth factor receptor (EGFR), an important receptor of tyrosine kinases in animals, plays versatile functions in development, growth and tissue regeneration. In this study, we described the characteristic and function of an EGFR gene identified from P. f. martensii(PmEGFR). PmEGFRpossesses a typical EGFR structure and is expressed in all studied tissues, with the highest expression level in adductor muscle. PmEGFRexpression level is significantly higher in the fast-growing group than that in the slow-growing one. Correlation analysis represents that shell height and shell weight show positive correlation with PmEGFRexpression (p < 0.05), and total weight and tissue weight exhibit positive correlation with it (p < 0.01). This study indicates that PmEGFRis a valuable functional gene associated with growth traits.

The effect of Sc on the microstructure and mechanical properties of Al–Si–Mg–Cu–Ti alloy was investigated. Results obtained in this research indicate that, with increasing Sc content, the microstructure of the investigated alloys exhibits finer equiaxed dendrites with rounded edges and the morphology of the eutectic Si shows a complete transition from a coarse needle-like structure to a fine fibrous structure upon modification of eutectic Si. Subsequent T6 heat treatment had further induced the precipitation of nano-scaled secondary Al3(Sc, Ti) phase, as well as spheroidisation of eutectic Si. Combined with T6 heat treatment, the ultimate tensile strength, yield strength, percentage elongation and hardness were achieved in 0.20?wt-% Sc-modified alloy.

In this study, we seek to explore the impact of a state level transmission expansion project, the Competitive Renewable Energy Zones (CREZ), whose goal is to integrate a massive amount of wind energy, on the wholesale market prices in the Electric Reliability Council of Texas (ERCOT). We find strong evidence for price convergence across ERCOT with accordance to the timing of the expansion of major sections of the CREZ. A variety of empirical analyses shows a gradual transition to a well-integrated market. We also find that regional-specific shocks became more important in terms of driving price change in other regions. Specifically, the impacts of Houston (demand) and the West (wind supply) on each other and the North and South regions have increased significantly. Our study contributes to the literature by connecting the expansion of physical transmission lines with electricity market integration

ABSTRACT:The Conservation Reserve Program (CRP), which provides incentives for landowners to idle erodible and marginal farmland, faced new challenges as record-high commodity prices significantly affected landowners' interests in the program in recent years. We develop and estimate an empirical structural model to examine the manner in which productivity, market conditions, and CRP payment affect landowners' land use decisions. The model carefully controls for the endogeneity of CRP payment and landowners' self-selection into the program. The parameter estimates are used to simulate how changes in agricultural prices and CRP payment influence program enrollment and cost across the Corn Belt states.

Mechanical strength is crucial to flexible supercapacitors during their practical usage. In this work, polybenzimidazole with a high tensile strength of [?]100 MPa, an anion (or proton) conducting polymer electrolyte when doped with KOH (or H3PO4), was employed to fabricate highly robust and flexible supercapacitors. The polybenzimidazole film was integrated with activated carbon electrodes coated on graphite paper. These flexible supercapacitors exhibited low equivalent series resistance and good cycling stability of capacitance retention above 90% after 10000 cycles. Under mechanical deformations of bending, twisting, and rolling as well as a repeated bending test, the electrochemical performance of the flexible supercapacitors was well maintained, demonstrating good flexibility. The integration design showed better reliability against mechanical damage. It is an advantage for flexible supercapacitors with high energy density in mass production especially for devices based on KOH doped polybenzimidazole. This work suggests that polybenzimidazole based ion conducting polymer electrolytes are very promising for developing highly robust flexible supercapacitors in future practical applications.

The activity of enzymes involved in digestion, energy metabolism, oxidative stress regulation, and immune function in the pearl oyster (Pinctada fucata martensii) was determined at 0, 0.5, 1, 2, 5, 10, 15, and 25 d following exposure to HG and NG to characterize the effects of hypoxia on pearl oysters. The protease activity was significantly higher in HG than in NG at 0.5 and 1 d but significantly lower in HG than in NG at 2, 5, 10, 15, and 25 d. The activity of amylase, lipase, and PK was significantly lower in HG than in NG at 0.5, 1, 2, 5, 10, 15, and 25 d. T-AOC and activity of CAT and LDH were significantly higher in HG than in NG at 0.5, 1, 2, and 5 d but significantly lower in HG than in NG at 10, 15, and 25 d. SOD and GPx activity was significantly higher in HG than in NG at 0.5, 1, 2, and 5 d and significantly lower in HG than in NG at 15 and 25 d. LPO content was significantly higher in HG than in NG at 0.5, 1, 2, 5, 10, 15, and 25 d. AKP activity was significantly lower in HG than in NG at 0.5, 1, 10, 15, and 25 d, but no differences in AKP activity were observed between HG and NG at 2 and 5 d. ACP activity was significantly higher in HG than in NG at 0.5 d and significantly lower in HG than in NG at 1, 2, 5, 10, 15, and 25 d. These changes in digestion, energy metabolism, antioxidant capacity, and immune defense promoted adaptation to early hypoxia. Long-term hypoxia decreased the survival rate of pearl oysters by decreasing involved in digestion, energy metabolism, immune responses, and oxidative stress regulation.

We analyzed the mantle transcriptome of pearl oyster Pinctada maximaand developed EST–SSR markers using Illumina HiSeq 2000 paired-end sequencing technology. A total of 49,500,748 raw reads were generated. De novoassembly generated 108,704 unigenes with an average length of 407 bp. Sequence similarity search with known proteins or nucleotides revealed that 30,200 (27.78%) and 25,824 (23.76%) consensus sequences were homologous with the sequences in the non-redundant protein and Swiss–Prot databases, respectively, and that 19,701 (18.12%) of these unigenes were possibly involved in approximately 234 known signaling pathways in the Kyoto Encyclopedia of Genes and Genomes database. Ninety one biomineralization-related unigenes were detected. In a cultured stock, 1764 simple sequence repeats were identified and 56 primer pairs were randomly selected and tested. The rate of successful amplification was 68.3%. The developed molecular markers are helpful for further studies on genetic linkage analysis, gene localization, and quantitative trait loci mapping.

The determination of the overall technology index is a key to the overall design of space manipulator. An overall performance indexes determination method of a space manipulator were presented. The dynamic simulation study was also performed. Firstly, considering the mission objectives and combining with the overall constraints, the main technology indexes, including manipulator length, end-effector positing and orientating accuracies, the maximum end-effector velocities, and joint drive torques, and so on, were demonstrated. Secondly, the multi-body dynamic model of a space robotic system was created. Based on this model, the manipulation process of the space robot carrying a payload under normal and extreme conditions was simulated. Simulation results show that the proposed ideas and methods are very useful for the development of the space robot system. [ABSTRACT FROM AUTHOR]

Motivated by strong comovement and increasing volatility of energy and agricultural prices, we examine dynamic evolutions of ethanol, gasoline, and corn prices over the period of March 2005-March 2011. A structural change is found around March 2008 in the pairwise dynamic correlations between the prices in a multivariate GARCH model. A structural VAR (SVAR) model is then estimated on two subsamples, one before and one after the identified change point. Using the novel method of identification through heteroscedasticity, we exploit the time-varying price volatilities to fully identify the SVAR model. In the more recent period, ethanol, gasoline, and corn prices are found to be more closely linked with a strengthened corn-ethanol relation, which can be explained by the new developments of the biofuel industry and related policy instruments. Variance decomposition shows that for each market a significant and relatively large share of the price variation could be explained by the price changes in the other two markets. The results are robust to the inclusion of seasonal dummies and various representative macroeconomic and financial indicators.

Based on an analytical model of multiple interconnected markets including corn, ethanol, gasoline, and transportation fuel, this study estimates the welfare changes for consumers and producers resulting from ethanol production and related support polices in 2007. The welfare estimation takes into account the fact that the ethanol program was implemented in a market that had already been distorted by other programs. The results suggest a total social cost of about $0.89 billion for given market parameters. We validate the model’s underlying assumption and test for the results’ sensitivity to assumed parameters.

The second-generation selected (SS) and control (SC) lines of the Chinese pearl oyster Pinctada martensiiwere established by selecting the 10% of breeders with the largest and mean sizes, respectively, from the first-generation selected group. Larval offspring of the SS and SC lines were reared at 30, 24, and 18‰. Heritability and genetic gains of larval shell length were estimated on the basis of data measured at days 8, 14, and 21. At days 8 and 14, there were no significant differences in mean shell length between the SS and SC lines at 30, 24, and 18‰ (P> 0.05). On day 21, however, the SS line displayed significantly larger mean shell length than the SC line at 30‰ and 24‰ (P< 0.05). Heritability estimates and genetic gains for larval shell length ranged from 0.22 to 0.64 and from 3.68% to 14.93%, respectively. The results from this study indicate that considerable genetic variability exists in the base population and that mass selection for the second generation is still effective.

Abstract: Three wild populations of Meretrix meretrix sampled from Dongxing, Beihai, and Shankou along the coast of Guangxi, China, were investigated with morphometry and karyometry. Six morphological indices (shell length, shell height, shell width, hinge length, total wet weight and shell weight) were measured. Differences in all morphological indices except hinge length were significant among the three populations (P < 0.05). The mean values of these indices (except for the hinge length) in the Dongxing population were larger than those in the Beihai and Shankou populations, although the latter had the largest hinge length. The karyotype of the Beihai, Shankou and Dongxing samples had ten metacentric, six submetacentric, and three subtelocentric chromosome pairs. No significant difference was shown in the centromeric index values of the chromosomes in the populations (P>0.05). However, the order of metacentric, submetacentric and subtelocentric chromosome pairs was variable among the three populations. The results indicate a high level of inter-population variation in morphology and karyotype.

•A total of 201 metabolites were identified from the serum of pearl oyster.•A total of 35 metabolites were revealed as SDM before and after transplantation.•Acetylcholine was up-regulated after transplantation.•Acetylcholine may function through nAChRs by inhibiting NF-κb signal pathway.

The exoskeleton outside the soft body in shelled Mollusca defends against physical damage and parasite invasion and frequently undergoes biological and abiotic disturbance in natural and farmed environments, causing shell damage and environmental exposure, thereby threatening survival. To investigate the immune response and biocalcification after shell damage in pearl oyster Pinctada fucata martensii, a semi-sessile bivalve with a well-developed shell structure, we constructed a shell damage repair model and detected the transcriptome of mantle edge. In the first stage (4–12h post-shell notching) the suppression of the secretion of the shell matrix protein (SMP) and activation of immune signaling pathways suggested the functional transformation of the mantle from biomineralization to immune defense. In the second stage (12–24h), the enhancement of protein synthesis and processing, protein export-related functions, and energy production-related pathways indicated that the mantle prepared materials and energy for repairing the damaged shell and tissues. In the third stage, the upregulation of 68 SMPs involved in the shell formation indicated the reopening of shell fabrication and the repair of mantle tissue cells from immune defense to biomineralization. Furthermore, some SMPs burdened immune response molecules and the controller of biomineralization, which indicated the crosslinking between immune response and biomineralization. Our research outlines three stages an individual suffers during shell damage and provides insights into immune response and biocalcification crosslinking in pearl oyster and improves understanding of how the mantle tissue can quickly respond to environmental threats.

Hepatic sinusoidal obstruction syndrome (HSOS) can be caused by the intake of pyrrolizidine alkaloids (PAs). The disease has a high mortality rate, a poor prognosis and limited treatment options. Managing pyrrolizidine alkaloid-induced hepatic sinusoidal obstruction syndrome (PA-HSOS) is a significant challenge for hepatologists. This case report describes five patients with PA-HSOS that were treated with low molecular weight heparin (LMWH) between 2014 and 2019. All five patients had a history of taking PA-containing herbal preparations before the onset of the disease. They all met the Nanjing diagnostic criteria and were diagnosed with PA-HSOS. Symptomatic treatment was administered to all five patients. In addition to symptomatic treatment, all five patients were treated with LMWH for approximately 8–21 days. After treatment, their ascites disappeared, symptoms improved and the hepatic venous blood flow had improved compared with before treatment. There was no obvious discomfort during the 6 months of follow-up. LMWH may play a useful role in the early treatment of PA-HSOS. Therefore, for patients in the early stages of PA-HSOS, in addition to symptomatic treatment, early anticoagulant intervention can be attempted to improve patient prognosis under close monitoring of coagulation.

•This work is the first to analyze alterations in the intestinal bacterial profiles of pearl oyster fed with formulated diets.•Diet with corn gluten as the main protein source led to a low biodiversity level.•A suitable protein source must be selected to ensure the intestinal health of P. f. martensii.