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Avian pathogenic Escherichia coli (APEC) is primarily responsible for causing septicemia, pneumonitis, peritonitis, swollen head syndrome, and salpingitis in poultry, leading to significant losses in the poultry sector, particularly within the broiler industry. The removal of the lpxL and lpxM genes led to an eightfold decrease in the endotoxin levels of wild APEC strains. In this study, mutant strains of lpxL / lpxM and their O1, O2, and O78 wild-type strains were developed for an inactivated vaccine (referred to as the mutant vaccine and the wild-type vaccine, respectively), and the safety and effectiveness of these two prototype vaccines were assessed in white Leghorn chickens. Findings indicated that chickens immunized with the mutant vaccine showed a return of appetite sooner post-immunization and experienced earlier disappearance of nodules at the injection site compared to those immunized with the wild-type vaccine. Pathological examinations revealed that lesions were still present in the liver, lung, and injection site in chickens vaccinated with the wild-type vaccine 14 days post-vaccination (dpv), whereas no lesions were found in chickens vaccinated with the mutant vaccine at 14 dpv. There were no significant differences in antibody levels on the challenge day or in mortality or lesion scores between challenged birds immunized with either the mutant vaccine or the wild-type vaccine at the same dose. In this study, the safety of a single dose or overdose of the mutant vaccine and its efficacy at one dose were evaluated in broilers, and the results showed that the mutant vaccine had no adverse effects on or protected vaccinated broilers from challenge with the APEC O1, O2, or O78 strains. These results demonstrated that the mutant polyvalent inactivated vaccine is a competitive candidate against APEC O1, O2, and O78 infection compared to the wild-type vaccine. [ABSTRACT FROM AUTHOR]

This study analyzed the microstructure and mechanical properties of a dual-phase Mg–Li alloy produced through submerged friction stir processing. The study focused on the recrystallization and grain refinement of distinct α-Mg and β-Li phases. Two methods were identified for refining the grains. The first method involved dynamic recrystallization in large deformed grains, resulting in recrystallized grains that had minimal impact on the two-phase distribution. The second method utilized a phase transition for the growth of new α-Mg and β-Li grains occurred through heterogeneous nucleation in the other phase. The relationship between the α-Mg and β-Li phases after the phase transition was observed to have an orientation of Mg[11–20]//Li[100], Mg(0–110)//Li(011). Maelstrom-affected zones were carefully observed near the advancing side, where severe recrystallization, phase transition, and second phase refinement occurred in this region. Submerged friction stir processing prevented grain growth due to a high density of phase boundaries and rapid heat dissipation. As a result, micro-nano grains were observed in the maelstrom-affected zone. The ductility of the interface was enhanced by the maelstrom-affected zone. Therefore, the maelstrom flow can improve mechanical performance through grain refinement and redistribution for dual-phase Mg–Li alloys during submerged friction stir processing. [ABSTRACT FROM AUTHOR]

Strain-induced phase transformation in a dual-phase Mg–Li alloy after a severe deformation has been investigated. β-Li phase was transformed into α-Mg phase as a consequence of large strain cold rolling. The morphology and density of the strain-induced phase could be controlled by slip activation in the β-Li phase. A multi-direction rolling procedure was designed to enhance phase transformation behavior. High density strain-induced phase refined phase structure and greatly promoted the yield strength of the material without a sacrificing the ductility. Strain-induced phase transformation is a potential method for improving the mechanical properties in dual-phase alloys. Image, graphical abstract [ABSTRACT FROM AUTHOR]

A sandwich structure of Mg alloy bulk consisted of two types of texture was fabricated by pre-twinning deformation. Its mechanical response and work hardening behavior during uniaxial compression were deeply analyzed to investigate the competition mechanism between basal slip and detwinning. Results showed that pre-twinning layer was a soft region. It undertook more than half of the strain by one third of the volume fraction of the bulk at the beginning of deformation. Slip behavior was significantly enhanced by detwinning and it took a more important role to coordinate local strain. Texture bonding promoted slip behavior in the grains exhibited "hard" orientations. Activation of detwinning behavior in pre-twinning region was mainly depended on basal slip behavior of their parents. [ABSTRACT FROM AUTHOR]

Abstract The effect of Zn (0–1 wt%) content on the aging behavior and mechanical properties of Mg 8Al 2Sn-xZn alloys have been investigated. The results indicated that addition of Zn promoted the age-hardening response and precipitation of the Mg 17 Al 12 phases through high grain boundary migration and the increase of the nucleation rate of Mg 17 Al 12 phases. The proportion of discontinuous precipitation zone in the Mg 8Al 2Sn 1Zn alloy was 37%, which was two times larger than that in the Mg 8Al 2Sn alloy without Zn. The discontinuous precipitation phases grew fast and were not suppressed by nano-size Mg 2 Sn phases. Both continuous and discontinuous precipitates were refined in the as-aged alloys with the addition of Zn. According to the yield strength calculation, fine precipitates with high density more effectively enhanced the strength in Mg 8Al 2Sn 1Zn alloy. The yield strength of the Mg 8Al 2Sn 1Zn alloy was increased by 24% after the aging treatment. The peak-aged AZT812 alloy exhibited mechanical properties that included a yield strength, an ultimate tensile strength and an elongation of 296 MPa, 408 MPa and 7%, respectively. [ABSTRACT FROM AUTHOR]

Abstract The microstructure and texture characteristics of commercial pure Ti after friction stir processing (FSP) with a slow rotation speed were studied. The shoulder friction zone (SFZ) which did not exist in the FSPed pure Ti with normal rotation speed (> 250 rpm) was observed in the sample treated with a slow rotation speed of 180 rpm. The texture of SFZ in the pure Ti was affected by shear stress from the shoulder of stir tool and the c-axes of the grains in this zone were nearly parallel to the processing direction. While crystallographic texture in the normal stir zone (SZ) were nearly perpendicular to the processing direction. The maximum depth of SFZ in the sample with 180 rpm was 1.2 mm, which decreased with the increased rotation speed until it disappeared. The grains in the SZ of specimen following FSP at a slow rotation speed were fine and homogeneous. The microhardness increased from 150.2 HV to 191.6 HV after FSP at 180 rpm. The microhardness trends were related to grain sizes, work hardening and texture evolution. The slow rotation speed processed alloy boosted the yield strength by 71.7% after the FSP. Highlights • Shoulder friction zone of pure Ti formed during FSP with a slow rotation speed. • Texture was not uniform in the thickness direction of FSPed pure Ti processed with a slow rotation speed. • Grain size decreased and microstructure homogeneity in thickness increased in pure Ti by FSP with a slow rotation speed. • Mechanical properties of pure Ti were developed after FSP with a slow rotation speed. [ABSTRACT FROM AUTHOR]

This paper presents a distributed optimisation algorithm based on one-point bandit feedback (OPBF) which enables the solving of energy management problems (EMPs) over directed networks. Unlike existing EMPs with known cost functions, the proposed online energy management approach considers a time-varying and unknown cost function, which creates sampling difficulty. To tackle this challenge, a random gradient-free oracle is constructed, allowing for the facilitation of output generation updates. This construction significantly mitigates the need for explicit expressions of the cost function. Furthermore, the proposed algorithm successfully enforces both the supply-demand balance constraint and the generation constraint in EMPs. In order to evaluate performance, this study introduces a performance index referred to as regret, which exhibits sublinear convergence. This finding provides additional evidence that the algorithm can achieve optimal output generation at a rapid convergence rate, subject to certain step-size conditions. Finally, the performance of the algorithm is verified on both a modified 6-bus system and an IEEE 162-bus system. The results demonstrate the effectiveness and efficiency of the proposed algorithm in solving EMPs over directed networks. [ABSTRACT FROM AUTHOR]

Hot compression deformation tests of AZ80 and AZ80-2 wt.% Sn magnesium alloys were performed on Gleeble-1500 at deformation temperature of 350 °C and strain rate of 0.1 s −1 to analyze the effect of Sn on the microstructure evolution. The results indicated that the addition of Sn promoted dynamic recrystallization and decreased flow stress during hot compression. Dynamic dissolution of discontinuous precipitation Mg 17 Al 12 phases was promoted and dynamic precipitation of Mg 17 Al 12 phases was suppressed in AZ80-2 wt.% Sn alloy. The quantity of Mg 17 Al 12 phases of thermally compressed AZ80-2 wt.% Sn alloy was less than that of AZ80 alloy. Texture intensity increased in AZ80-2 wt.% Sn alloy during hot compression due to Mg 17 Al 12 phases effectively induced particle-stimulated nucleation in recrystallization. [ABSTRACT FROM AUTHOR]

T6 aging treatment was performed at 423 K and 473 K for AZT802 wrought magnesium alloy. To understand the effects of temperature on the aging behavior and mechanical properties, microstructure and uniaxial tensile performance at room temperature were studied. Aging temperature obviously affected the rate of precipitation. Temperature sensibilities of continuous precipitates and discontinuous precipitates were different and continuous precipitates were far more sensitive phases. With increasing aging temperature, continuous precipitates grew coarsely. Meanwhile, densities of continuous precipitates and part of discontinuous precipitates decreased rapidly. Mechanical properties and fracture analysis indicated that compact second phases reinforced matrix effectively. Cracks extended mainly through zones of discontinuous precipitates in the sample which was aged at 423 K. But when the aging temperature raised to 473 K, the sample tended to fracture mainly along zones of continuous precipitates and coarsely discontinuous precipitates. [ABSTRACT FROM AUTHOR]

The microstructure and mechanical properties of AZ80 wrought magnesium alloys with varying Sn contents (0, 1, 2 and 4 wt.%) have been studied by thermodynamic and precipitation kinetics calculation and examined using scanning electron microscopy (SEM), transmission electron microscopy (TEM), hardness test and uniaxial tensile test at room temperature in this paper. The results of thermodynamic and precipitation kinetics calculation showed that the precipitation sequences were determined by the content of Sn element. It was found that in the aging treatment of this work, Mg 17 Al 12 phase precipitated sooner than Mg 2 Sn phase in the alloys with less than 1.72 wt.% Sn and there was a contrary precipitation sequence of these two phases in the alloys with more than 1.72 wt.% Sn. Experimental results were in agreement with those of calculation. According to SEM and TEM observation, Sn promoted precipitation of Mg 17 Al 12 on aging temperature, however the preferential Mg 2 Sn phase suppressed discontinuous Mg 17 Al 12 precipitates by hindering the growth of these in their growth direction. AZ80 with 1–2 wt.% Sn as-aged alloys exhibited outstanding mechanical property that UTS, YS and EL were ∼420 MPa, ∼290 MPa and ∼5%, respectively. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) was successfully performed on ultra-light dual-phase LZ91 Mg Li alloy, which provided a chance to study the microstructure and texture evolution of this alloy during severe plastic deformation. The results showed that LZ91 Mg Li alloy could be processed successfully with 200–400 rpm, 25 mm/min, and water cooling during FSP. No defects were observed on the surface and in the cross-section. The microstructure was strongly influenced by the material flow modes during FSP. Two greatly phase refinement regions were found in the stir zone where the α-Mg and β-Li phases were refined to submicron scale and homogeneously mixed. Maelstrom currents flow between two threads on the pin triggered this phase fragment. The high rotation rate of FSP leads to a remarkable recrystallization and grain growth due to the high heat input. The severe plastic deformation caused a phase transformation inside the refined α-Mg phase. The new phases enriched Li element exhibited a coherent relationship with the matrix. It shows that FSP promoted the short-term diffusion in refined α-Mg. • Two phases in dual-phase Mg Li alloy were refined to submicron scale and distributed evenly after FSP. • Materials flow modes strongly influenced the grain refinement and phase distribution in FSPed Mg Li alloy. • A phase transformation inside refined α-Mg phase was discovered and analyzed. [ABSTRACT FROM AUTHOR]

The afterglow data of gamma ray bursts (GRBs) can be used to constrain the physical properties of the fireball (e.g., the jet structure and opening angle) and the circumburst medium. With the peak time of the early afterglow light curve being taken as the deceleration time, one can estimate the initial Lorentz factor of the fireball. In this work, we perform a comprehensive analysis on the prompt emission and the afterglow data of GRB 181110A, where a clear peak is detected by Swift UVOT and XRT in optical to X-ray bands. Prompt emission spectral analysis shows that the spectrum of GRB 181110A is soft, and both hard-to-soft and intensity-tracking spectral evolution are found. By fitting the afterglow light curve and building spectral energy distribution, we find that the standard external forward shock model with a constant circumburst medium is favored, and the jet structure of GRB 181110A tends to be uniform rather than structured. With the peak time of early afterglow emission, we estimate the initial fireball Lorentz factor of GRB 181110A to be Γ 0 = 169 − 40 + 92 . We also compare GRB 181110A with other typical long GRBs in a statistical context. [ABSTRACT FROM AUTHOR]

The dried and pulverized medical solid waste was pyrolyzed at 500 °C, and the components and characteristics were analyzed after the solid, liquid and gas products were collected respectively. Experimental results showed that the combustible component in the obtained gas product accounted for 83.22% and the heat value was 10,995.02kcal/Nm3. The liquid product obtained was black viscous tar with a heat value of 8972.82 kcal/kg, GC/MS analysis indicated that hydrocarbons and lipids accounted for about 60% of liquid product, and the carbon chain length of the products is C 6 –C 28. The carbon content of solid product after purification was up to 63.13%, and the heat value was 5454.54 kcal/kg. Furthermore, in order to make the most of the pyrolysis oil, the liquid product was separated and purified by fractional condensation under the condition of decompression. The effect of process parameters such as vacuum degree and condensing temperature was emphasized, and the optimum technological condition was obtained as follows: vacuum degree 0.04 MPa, heating temperature 140 °C and the first stage condensing temperature was 70 °C. Finally, the viscosity measurement of the residual high-viscosity components was intended to provide data support for the solution of tar plugging equipment and piping problems in practical applications. • Mixed medical waste was selected as pyrolysis raw materials. • The heat value of gas and solid products were 10,995.02kcal/Nm3 and 5454.54 kcal/kg. • The oil was reprocessed by fractional condensation to obtain the optimum condition. • This study provides a reference for the high-value utilization of medical waste. [ABSTRACT FROM AUTHOR]

Polyamidoamine (PAMAM) dendrimers grafted Polyacrylonitrile (PAN) UF membrane (PAN-PAMAM) was prepared for the first time. The optimized PAN-PAMAM membrane showed both a high flux (420 L m−2 h−1.bar−1) and a good BSA rejection (99%). To improve its hydrophilicity, the membrane was further modified with ethanolamine (ETA) under different conditions. The results suggest that PAN-PAMAM membrane modified by ETA/NaOH has an improved antifouling property for sodium alginate (SA), humic acid (HA) and bovine serum albumin (BSA), the flux recover ratio (FRR) increased from 61% to above 91%. Moreover, the modified membrane shows a better antifouling property in phosphate-buffered saline (PBS) solution than in water solution. DLS results showed that BSA aggregate morphology are different in two solutions. AFM image and BSA adsorption revealed that PBS decreases the coverage and amount of BSA adsorbed on the membrane surface, leading to an improved antifouling property. Surface tension and XDLVO theory were further used to analyze the fouling process. It was found that ETA/NaOH modification greatly increases the Lewis acid-base interfacial interaction of membrane. However, after the adsorption of BSA, Lewis acid-base interaction decreases greatly, leading to the irreversible fouling of membrane. Image 1 • PAMAM grafted PAN UF membrane with good performance was prepared for the first time. • ETA/NaOH modification further reduced BSA adsorption and improved antifouling property. • PBS solution reduced the coverage and amount of adsorbed BSA on membrane surface. • XDLVO theory analysis shows the adsorbed BSA reduces the Lewis AB interfacial interaction. [ABSTRACT FROM AUTHOR]

Background. Porcine epidemic diarrhea virus (PEDV) is an important pathogen causing highly contact infectious intestinal infections in pigs belonging to the family Coronaviridae, genus Coronavirus, which can cause porcine epidemic diarrhea (PED). Since 2010, outbreaks of PEDV variants have caused great economic losses to the swine industry worldwide. Our study will provide the basis for discovering the key points of PEDV variation and help in understanding the trend of popularity and evolution of PEDV in China. Methods. We amplify the complete PEDV CH/JSXZ/2015 genome sequence from naturally infected piglets in Xuzhou, Jiangsu Province, China, by RT-PCR. The comparative genome circle graph, characterization and phylogenetic analysis, and recombination in the PEDV CH/JSXZ/2015 and other PEDVs are analyzed by bioinformatics analysis software. Results. At the whole-genome level, CH/JSXZ/2015 showed the highest nucleotide identity (99.5%) with CH/GDZHDM/1401 strain (KR153326.1 and KX016034.1) and the lowest similarity (93.5%) to 85-7-mutant1 strain. CH/JSXZ/2015 S amino acid identity was 90.8%–99.8% compared with other strains. CH/JSXZ/2015 ORF3 amino acid identity was 91.2%–100.0% compared with other PEDV strains. Phylogenetic analysis based on the whole genome, S, and ORF3 revealed that CH/JSXZ /2015 is most genetically close to the CH/GDZHDM/1401 strain (KR153326.1 and KX016034.1) isolated in China in 2014. In addition, we revealed that the CH/GDZHDM/1401 (KX016034.1) strain, PEDV 1842/2016 ITA, and CH/JSXZ /2015 had recombination, and the position of recombination was 1–5530 and 28185–28544 bp. 5531–28184 bp of JSXZ are highly homologous to CH/GDZHDM/1401 (KX016034.1), while 1–5530 and 28185–28544 bp of JSXZ are highly homologous to 1842/2016 ITA. These results helped discover PEDV variation rules and provided a basis for preventing and controlling PEDV. Conclusions. Our study revealed that PEDV CH/JSXZ/2015 was a variant strain, the current epidemic strain in China. The CH/GDZHDM/1401 (KX016034.1) strain, PEDV 1842/2016 ITA (KY111278) and CH/JSXZ /2015 had recombination. [ABSTRACT FROM AUTHOR]

Summary: In this study, sawdust was selected as the raw material for biomass pyrolysis to obtain organic products. The catalyst was modified with two elements (Fe and Zn). Through analysis of the catalytic products, we attempted to identify a pyrolysis catalyst that can improve the yield of aromatic hydrocarbon products. ZSM‐5, modified with Fe and Zn, was investigated by X‐ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, and Brunauer–Emmett–Teller (BET) measurements. Tube furnace and flash pyrolysis‐gas chromatography‐mass spectrometry (Py‐GC/MS) were used to comprehensively investigate the characteristics of the products of biomass pyrolysis. The highest yield of phenols was obtained using the Fe‐modified ZSM‐5 catalyst, which was 18.30% higher than the yield obtained by the pure ZSM‐5 catalyst. The lowest yield of acid products was obtained by single‐metal‐supported catalytic pyrolysis with Fe or Zn, which was 50.66% lower than the yield obtained by direct pyrolysis. During the pyrolysis of biomass using metal‐modified catalysts, the production of aromatic hydrocarbons was greatly improved. Among them, compared with direct pyrolysis, the Fe‐Zn co‐modified ZSM‐5 catalyst exhibited the weakest promotion of aromatic hydrocarbon formation, but there was still a 68.50% improvement. Although the co‐modified catalyst did not show absolute advantages under the conditions used for this experiment, the improvements in the production of aromatics and phenolic products also showed its potential for improving bio‐oil products. Under the action of Fe‐modified catalysts, the most abundant components in the gas product were CO and CO2, which reached levels as high as 53.45% and 15.34%, respectively, showing strong deoxidation capabilities. Therefore, Fe‐modified ZSM‐5 catalysts were found to better promote the formation of aromatic hydrocarbon products of biomass pyrolysis. [ABSTRACT FROM AUTHOR]

Research evaluating predictors of mathematics ability in preschoolers with autism spectrum disorder (ASD) is scarce and inconclusive. The present study first compared the mathematics ability and cognitive abilities of preschoolers with ASD and age-matched typically developing (TD) peers. Then, we examined the relative contributions of cognitive abilities to the mathematics ability of preschoolers with ASD and TD. The results show that compared to those of their age-matched TD peers, the mathematics and cognitive abilities of preschoolers with ASD were impaired. The predictors of mathematics ability were found to differ among preschoolers with ASD and their age-matched TD peers. For TD preschoolers, the domain-specific approximate number system (ANS) was the key predictor of mathematics ability. For preschoolers with ASD, domain-general working memory (WM) was most important. [ABSTRACT FROM AUTHOR]

Highly efficient visible-light-driven heterojunction photocatalysts, spindle-shaped nanoporous TiO 2 coupled with graphitic g-C 3 N 4 nanosheets have been synthesized by a facile one-step solvothermal method. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), energy dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption analysis and UV–vis diffuse reflectance spectrometry (DRS), proving a successful modification of TiO 2 with g-C 3 N 4 . The results showed spindle-shaped nanoporous TiO 2 microspheres with a uniform diameter of about 200 nm dispersed uniformly on the surface of graphitic g-C 3 N 4 nanosheets. The g-C 3 N 4 /TiO 2 hybrid materials exhibited higher photocatalytic activity than either pure g-C 3 N 4 or nanoporous TiO 2 towards degradation of typical rhodamine B (RhB), methyl blue (MB) and methyl orange (MO) dyes under visible light (>420 nm), which can be largely ascribed to the increased light absorption, larger BET surface area and higher efficient separation of photogenerated electron–hole pairs due to the formation of heterostructure. In addition, the possible transferred and separated behavior of electron–hole pairs and photocatalytic mechanisms on basis of the experimental results are also proposed in detail. [ABSTRACT FROM AUTHOR]

Peanut shells were used as raw materials, and the synergistic effects of various acid pretreatments and catalytic pyrolysis for biomass were comprehensively studied. The results showed that the oil yield of 0.5 mol/L hydrochloric acid treatment was 44.75 wt%, and that of 0.5 mol/L acetic acid treatment was 43.40 wt%. The solid products decreased apparently after pretreatment. Acid-washing pretreatment and the subsequent catalytic pyrolysis of the pretreated biomass promoted the yield of aromatic in bio-oil. The yield of bio-oil gradually decreased while the gas yield increased with the increase of catalytic pyrolysis temperature. Ketones and anhydrosugars were also reduced in the bio-oil, while aromatics increased significantly, reaching the highest value of 19.62 wt% (0.5 mol/L hydrochloric acid treatment) and 19.30 wt% (0.5 mol/L acetic acid treatment) respectively at 600 ℃. Synergy effect facilitated the conversion of pyrolytic intermediates to gas and aromatics. Besides, the possible formation mechanism of bio-oil under different pyrolysis conditions is proposed. The study indicates the optimized combination could effectively improve the quality of bio-oil. [Display omitted] • Pretreatment reduce acids and ketones and contribute to the generation of sugars (27.25 wt%). • Acid-washing and catalyst synergistically promote the yield of aromatic in bio-oil. • Anhydrosugars from pretreatment are important raw materials for aromatization. • Bio-oil yields (44.75 wt%) were obtained after 0.5 mol/L hydrochloric acid treatment. [ABSTRACT FROM AUTHOR]

Twinning was regarded as an effective way to modify the precipitation in Mg alloys. Two procedures were designed to illustrate twinning-aging consequence on Mg 17 Al 12 phase evolution. The effect of multiple steps of twinning-precipitation on the morphology and density of the continuous precipitates inside the twins and the matrix were comprehensively analyzed through phase-orientation related observation. The results show the shape of precipitates in twins was similar to that in the matrix as the CPs mostly lay on the basal planes with an asymmetric-lozenges shape. The CPs were remarkably refined and its density became much higher inside twins. Moreover, the aspect ratio of the CP plates in twins was around 45% of that in the matrix, which means the CPs inside twins became more globular. The precipitation behavior of Mg 17 Al 12 phase inside double extension twins was different from the primary twin or the matrix. The Mg 17 Al 12 phases lay on both basal and prismatic planes can be observed in double twins of two-step precipitation. The growth behavior of pre-precipitates in twins is different from those in the matrix. The growth rate along its thickness became higher than that in the matrix, which is probably related to dislocation-assisted diffusion at the basal plane. • Morphology of CPs precipitated in the matrix, primary and double twins is different • Ratio of length and thickness of CPs in twins significantly decreased • CPs lay on basal and prismatic planes are prepared in one twin structure • Dimension of CPs precisely characterized by phase-orientation related observation [ABSTRACT FROM AUTHOR]

The Incoloy 945 nickel-based corrosion-resistant alloy was subjected to a low-temperature solid solution with a two-step aging process to fabricate a bimodal grain structure. The study investigated the mechanism behind the formation of the bimodal grain structure and its impact on mechanical properties. The results show that numerous clusters of fine grains, with an average size of 4 μm, were formed among the normal grains, which had an average size of 23 μm. The precipitation behavior in fine-grain clusters differs from that in normal grains. A high density of rod-like δ phases tends to precipitate inside refined grains. The inhomogeneous precipitation of δ phases is the main reason for the formation of fine-grain clusters because they have a strong ability to pin the grain boundaries for the growth of new recrystallized nuclei. The morphology of γ' varies from short rod-like particles to spherical particles depending on their location in fine-grain clusters or normal grains. The difference in precipitation and grain structure leads to different deformation mechanisms in the two regions. The bimodal grain structure results in higher strength and work hardening rate during tension. The quasi-in-situ tensile test indicates that slip transfer is more easily induced in fine-grain clusters. Fine grains had an advantage in accumulating necessary geometric dislocations during deformation, resulting in a high work hardening rate for this bimodal grain structure sample. • Bimodal grain structure with fine grain clusters formed during the two-step aging. • Inhomogeneous precipitation of δ phase causes the formation of fine grain cluster. • Segregation of Nd atoms is responsible for bimodal grain structure. • Change of precipitation behavior enhance work hardening rate in fine grain clusters. [ABSTRACT FROM AUTHOR]

The infection of porcine circovirus type 2 (PCV2) triggers activation of the protein kinase RNA–like endoplasmic reticulum kinase (PERK) pathway and leads to DNA damage. Insulin-like growth factor-binding protein 3 (IGFBP3) may interact with the endoplasmic reticulum (ER). It remains unclear whether IGFBP3 regulates DNA damage via ER stress to mediate PCV2 replication. In this study, we observed an upregulation of porcine IGFBP3 expression during PCV2 infection, and overexpression of IGFBP3 enhanced the expression of PCV2 Cap protein, PCV2 DNA copy number, and viral titers in PK-15 B6 cells and 3D4/21 cells. Additionally, overexpression of IGFBP3 induced an increase in the DNA damage marker γH2AX by activating the PERK/eIF2α pathway without concomitant activation of ATF4, IRE1α, and ATF6α/GRP78 pathways in PK-15 B6 cells and 3D4/21 cells. Knockdown of IGFBP3 had a reverse effect on PCV2 replication in PK-15 B6 cells and 3D4/21 cells. Furthermore, treatment with etoposide enhanced PCV2 replication while KU57788 decreased it. GSK2606414 and salubrinal limited both DNA damage and viral replication. Therefore, our findings suggest that porcine IGFBP3 promotes PCV2 replication through the PERK/eIF2α pathway-mediated induction of DNA damage in PK-15 B6 cells and 3D4/21 cells. Our study provides a basis for exploring novel antiviral strategies via the extensive understanding of the relationships between host cellular proteins and viral replication. • Porcine IGFBP3 expression upregulated in PK-15 and 3D4/21 cells upon PCV2 infection. • Overexpression of IGFBP3 increased DNA damage and PCV2 replication through PERK/eIF2α signaling. • Knockdown of IGFBP3 suppressed DNA damage, PCV2 replication by inhibiting PERK/eIF2α signaling. [ABSTRACT FROM AUTHOR]

Highlights • p ompT gene is likely to play an important role in the virulence of APEC strain E058. • λ red recombination system have side-effects on E. coli mutant construction. • An unexpected transcriptome pompTʹ emerged in mutant E058Δp ompTʹ. • Pathogenicity of E058Δp ompTʹ was higher than that of E058Δp ompT. Abstract The lambda red recombination system makes it suitable for screening virulence gene utility in avian pathogenic Escherichia coli (APEC) on account of its wide applicability, simplicity and high efficiency. In APEC E058 (O2 serogroup), there are two copies of the outer membrane protease (ompT) gene, c ompT encoding cOmpT that is located on the chromosome and p ompT encoding pOmpT that is located on a ColV plasmid. However, the relationship between pathogenesis and p ompT expression in APEC E058 has yet to be elucidated. Here, we successfully constructed two p ompT gene mutants: E058Δp ompT containing a chloramphenicol (cat) resistance gene and E058Δp ompTʹ without the cat gene. By RT-PCR and sequencing analysis, an unexpected transcriptome p ompTʹ was detected in mutant strain E058Δp ompTʹ after deletion of the cat gene induced by the lambda red recombination system. Surprisingly, the pathogenicity of mutant E058Δp ompT was significantly attenuated compared to its parental strain in the chicken infection model and HD11 cell model then the p ompT gene was knocked out, while the pathogenicity of the other mutant strain E058Δp ompTʹ had no difference. Furthermore, the presence of unexpected transcriptome p ompTʹ influenced the bactericidal activity of SPF chicken serum and decreased the transcription level of TLR2 in the heart tissue of chickens. Our study identifies the p ompT gene plays an important role in the virulence of APEC E058, and the unexpected transcriptome p ompTʹ contributes to the increased pathogenicity of APEC E058 mutants following deletion of the cat gene induced by the lambda red recombination system, which suggests that this system still has some limitations for construction of mutant strains particularly where these are used in development of live vaccine. [ABSTRACT FROM AUTHOR]

Effect of Al addition on microstructure and texture evolution during hot rolling of Mg alloys was investigated using Mg-(3, 6 and 9 wt%)Al-Zn series alloys. The results showed deformation behaviors, including twinning, dynamic recrystallization and activation of slip system, were affected by the increase of Al content. Compared with AZ31 Mg alloys, the rolled AZ91 sample exhibited strong basal texture and intensity of basal texture decreased by increasing rolling strain. Unlike double twins and contraction twins which were commonly observed in the hot rolling of AZ31 Mg alloys, twinning behavior was strongly suppressed by the addition of Al content. It was observed some grain-like extension twins nucleated inside unrecrystallized grains with ultrafine size in AZ91. The size of dynamic recrystallized grains in AZ91 was ultrafine compared to that of AZ31 due to pinning effect produced by small Mg 17 Al 12 particles. These recrystallized grains were distributed along grain boundaries and would continuously coordinate further deformation strain after their nucleation. The increase of the area fraction of recrystallized grains resulted in a texture weakness during large strain rolling in AZ91. Geometrically necessary dislocation information was analyzed for the rolled samples. It showed prismatic slip took an advantage in AZ31 rather than AZ91 during hot rolling, which may be a reason for the weaker basal texture of unrecrystallized grains in AZ31. [ABSTRACT FROM AUTHOR]

Commercial AZ31 Mg alloys sheet was hot rolled by 50% thickness reduction in a single pass. The rolling process was manually interrupted before the entire sheet was rolled, and an intermediate-rolled sample was obtained. The microstructure, texture and mechanical responses on both surface and mid-layer of the intermediated-rolled sample were investigated. Our results show that the thickness gradients of microstructure and texture of as-rolled sheet were mainly caused by heterogeneously severe deformation when the surfaces of the sheet were bitten by the rollers. Both discontinuous and shear bands related dynamic recrystallization were observed. The recrystallized grains inside shear bands first nucleated in twins. The refined grains exhibited a strong basal texture with random distribution of 〈 11 2 ¯ 0 〉 direction. Discontinuous release of deformation strain during hot rolling led to strain flow localization, which resulted in formation of shear bands. Shear bands helped to coordinate the strain distribution between two nearby regions to prevent cracking in large strain rolling. [ABSTRACT FROM AUTHOR]

The effect of pre-twinning process on dynamic recrystallization, texture and mechanical properties of Mg alloys sheets was investigated by rolling pre-compressed AZ31 Mg sheets at 350 °C. Two types of pre-compressed sheets with different initial texture component were rolled by 60% thickness reduction in a single pass for observation. Microstructure, texture and mechanical properties evolution during large strain rolling were carefully investigated. The results show that dynamic recrystallization is greatly promoted by pre-compression process. Twin structures are more effective in enhancing dynamic recrystallization than pre-deformation strain stored during compression. Besides slip, detwinning is regarded as an important deformation mode when pre-twinning samples are rolled along their compression directions. Low temperature annealing of pre-twinning samples prior to rolling hinders detwinning process, resulting in an increase of yield stress. The basal texture and plane-anisotropy are greatly weakened in the sample rolled perpendicular to the pre-compression direction. The mechanical properties of rolled sheets were promoted by pre-twinning process. [ABSTRACT FROM AUTHOR]

Laser surface remelting (LSR) was performed on a Mg-6.2Y (at.%) magnesium alloy to enhance mechanical properties of its surface. The results show that both grains and secondary phase were greatly refined by LSR. The ε phase (Mg 24+ x Y 5) was redistributed from α -Mg grain boundaries to interior of the grains. The Y content of ε phase decreased from 14.3 to 9.3 at.% due to the LSR. Some metastable Y-rich nano particles were formed on the ε phase due to the rapid solidification. Mechanical properties of treated surface were significantly improved due to grain refinement and phase redistribution. Compressive strength of the treated region was increased to 606 MPa and exhibited a moderated ductility compared to the initial material. The increase of ductility by LSR is related to the uniformed redistribution of ε phase, which led to a homogeneous distribution of strain. [ABSTRACT FROM AUTHOR]

Strain-induced dynamic precipitation of Mg 17 Al 12 phases was observed in large strain hot rolling of Mg–8Al alloys sheets. Our results show that Mg 17 Al 12 phase precipitates in dynamic recrystallization of grains due to severe plastic deformation and the amount of secondary particles increases with increasing deformation strain. Two types of nanoscale Mg 17 Al 12 phases precipitated inside dynamic recrystallized grains were observed. The growth of dynamic recrystallized grains is constricted by the pinning effect of β phase. The mechanical properties of rolled sheets are largely influenced by the increase of the deformation strain. It shows that the increase of ultimate tensile strength of rolled sheets can be segregated into two different stages, which are similar to the enhancement of dynamic recrystallization. The tendency of mechanical properties evolution of rolled sheets reveals that strain-induced precipitates have excellent hardening behavior and it can be considered as a promising way in improving mechanical properties of Mg alloys. [ABSTRACT FROM AUTHOR]

The effects of Nd addition on the microstructure and mechanical properties of Mg–6Zn–1Mn–4Sn alloy have been investigated. The results show that α-Mg, α-Mn, Mg 7 Zn 3 , Mg 2 Sn and MgSnNd phases are found in the as-cast Nd-containing alloys. The MgSnNd phase is a high temperature phase which can enhance the age hardening response of the heat-treated alloys. The ZMT614–1.5Nd alloy under the extruded and aged states exhibits higher strength. This is mainly attributed to the fine grains after extruding and high number density of rod-shaped β 1 ′ precipitates in the α-Mg matrix after aging, respectively. [ABSTRACT FROM AUTHOR]

Hot rolling with three different rolling thickness reductions (20%, 40% and 70%) was carried out by single rolling pass on AZ31 Mg alloy sheets at three different rolling speeds varying between 3.5 and 12.1 m/min. The evolutions of the microstructure and mechanical properties of the hot rolled samples were critically examined. The results showed that twinning was the dominant deformation behavior during hot rolling at small rolling reduction and secondary twinning was the main way of twinning in this rolling condition. At high rolling speed, dynamic recrystallization can be activated and further enhanced by increasing thickness reduction. As the microstructure was refined, both strength and ductility of the samples were improved by dynamic recrystallization. While no obvious dynamic recrystallization was investigated during hot rolling at low rolling speed, twinning was further enhanced by increasing thickness reduction at this speed, resulting in an increase in yield strength and a remarkable reduction in ductility. [ABSTRACT FROM AUTHOR]

Abstract: The influence of the rolling speed on microstructure and mechanical properties of as-rolled AZ31 Mg alloys sheet was critically examined. Samples were hot rolled by nearly 55% thickness reduction in a single rolling pass at rolling speeds varying between 3.5 and 12.1m/min. The results showed that twinning dominated the deformation at lower rolling speed and dynamic recrystallization was constricted in shear bands. While, at high rolling speed, dynamic recrystallization behavior was largely extended and microstructure became homogeneous. The yield behavior of as-rolled sheets was affected by the recrystallized grains formed during rolling. The tensile ductility was gradually improved as rolling speed increased, due to the enhancement of dynamic recrystallization. The dynamic recrystallization is an effective way to consume the deformation energy, which may suppress edge crack initiation. [Copyright &y& Elsevier]

AA2099 Al-Cu-Li alloys were rolled by both asymmetrical and conventional rolling to a total thickness reduction of 80% at room temperature. Microstructure and texture evolution through thickness of rolling sheets were comprehensively investigated. Results show that large shear stress in ASR sample gave rise to a distortion of grain structure and a remarkable work hardening at region close to fast rolled surface. Shear banding behavior was largely promoted by ASR and various types of shear bands with higher density were observed. The shear bands triggered a kink of grain structure during rolling process. The kink behavior was related to the tilt angle and width of shear bands. The shear bands exhibited large tilt angle and width gave rise to a more significant kink of the grain structure nearby. Recrystallization during subsequent annealing was also promoted by ASR. Shear bands became favorable nucleation sites for rolled material. Growth advantage of some nuclei inside shear bands had a stronger influence on the recrystallized texture in AA2099 rolled sheets. • Asymmetrical rolling brought inhomogeneous microstructure and texture through thickness. • Grain structure was kinked into several parts due to formation of shear band. • Kink behavior is depended on the direction and the width of shear bands. • Shear banding nucleation triggers uncommon recrystallized texture during annealing. [ABSTRACT FROM AUTHOR]

• Nanocrystalline structure was produced by cryogenic rolling in an AA 2099 alloy. • Ultrafine structure was observed inside or near the regulate-oriented shear bands. • Severely deformation and related temperature increase leads to the grain refinement. • Shear banding was promoted due to strong work hardening at cryogenic temperature. Solid solution treated AA 2099 alloy was rolled by a total reduction of 80% at both room and cryogenic temperature. Results show that nanocrystalline grain structure with a size around 20–100 nm was only observed in the cryogenic temperature rolled sample at high rolling strain. The formation of those nanograins related to shear banding behavior. Shear banding behavior was greatly promoted by cryogenic temperature rolling, which had a strong influence on mechanical homogeneity of rolled samples. The width of these high-density shear bands is around 0.2–8 µm. Shear strain partitioning between slip and shear banding was depended on slip behavior in deformed grains. Strain concentration inside shear bands may give rise to an obvious temperature increase, which caused significant grain refinement in or near the shear bands. The growth of nano-grains is retarded due to limited heat and pinning effect of nanosized precipitation. [ABSTRACT FROM AUTHOR]

Molecular separation of dye mixtures containing the same charge remains a challenge. In the present study, we prepared a composite membrane that could efficiently separate anionic dye mixtures. Briefly, Al-Metal-organic framework (Al-MOF) nanoparticles synthesized by the ion-exchange method were used as fillers during the in-situ synthesis of ethanolamine (ETA) grafted polyacrylonitrile (PAN) membrane. The optimized composite membrane showed a high rejection of congo red (CR) from a single solution (96% rejection) and the CR/methyl orange (MO) mixture (93%/18%) solution. The flux of dye mixture solution reached 180 L m−2 h−1, higher than many reports in the literature. The further modification on pore size (heat treatment) or surface charge (hydrolysis treatment) improved the membrane performance to separate smaller dye mixture of methyl blue (MB)/MO. Both modified membranes showed a good MB rejection (93%) and flux of 70–85 L m−2 h−1. While for the separation of the MB/MO mixture, the heat-treated membrane showed the lowest flux and a middling rejection. The surface hydrolyzed membrane showed a better selectivity (96% MB/32% MO) and a higher flux (127 L m−2 h−1) than that of the entirety hydrolyzed membrane (93% MB/58% MO and flux of 78 L m−2 h−1), which was attributed to their different charge distribution. Image 1 • Al metal-organic framework prepared by ion-exchange method was used as filler. • Congo red/methyl orange mixture was separated by the composite membrane. • Membranes modified by pore size or charge separate methyl blue/methyl orange. • Charge distribution of membrane greatly affects its dye separation performance. [ABSTRACT FROM AUTHOR]

Microstructure evolution of severely cold rolled dual-phase Mg–Li alloy during annealing at various temperatures was systemically investigated. The results showed that severely deformed α-Mg phase can be significantly refined by annealing process. α-Mg phases were first stratified into various layers by phase transformation from α-Mg phase into β-Li phase. Low angle grain boundary was more easily inducing phase transformation compared to high angle one during annealing. α layers continuously broken into chains of α grains at high annealing temperature, which is controlled by the motion of triple junction at the intersection of phase and grain boundary. Grain boundaries exhibited a high interface tension compared to phase boundary, which drove the globularization of α-Mg grains. Mechanical properties and strain hardening behavior were influenced by phase refinement. Coordination of grain refinement and phase refinement promoted the ductility of dual-phase Mg–Li alloy without a remarkable decrease in strength. [ABSTRACT FROM AUTHOR]

Microstructure and texture evolution of Mg-8.8 wt%Li-0.8 wt%Zn dual-phase alloy during cold rolling to 70% thickness reduction were investigated. The results showed that both α-fiber and γ-fiber of β-Li phase were enhanced during the cold rolling procedure and {001}<110> was the dominant texture component. A double-peak texture with a large tilt angle of 28° was observed in α-Mg phase. Each peak of this texture component exhibited a wider orientation spread towards the transverse direction. This spread is related to the strong activation of pyramidal II slip. Basal slip was still the dominant slip mode and the activities of pyramidal I and pyramidal II slip were also largely enhanced. Schmid factor analysis and viscoplasitc self-consistent simulation jointly suggests that the development of the rolling texture in α-Mg phase can be ascribed to the competition between basal slip and pyramidal slip. • Second order pyramidal slip was promoted in the dual-phase structure Mg–Li alloy. • Pyramidal II slip has a stronger impact on texture compared to pyramidal I slip. • Two stable rolling texture components were found in the α-phase. • Competition of basal and pyramidal slip has a strong impact on texture development. [ABSTRACT FROM AUTHOR]

Bacterial communities of biofilms growing on artificial substrates were examined at two time periods (7 and 14 days) and two locations (lentic and lotic areas) in a hypereutrophic urban river of eastern China. Previous studies in this river network indicated that variations of microbial communities were the major factor affecting the distribution of antibiotic resistant genes highlighting the importance of understanding controls of microbial communities. Bacterial communities associated with biofilms were determined using epifluorescence microscopy and high-throughput sequencing. Results showed that sampling time and site had significant effects on the abundances of surface-associated bacteria. No significant differences were found in the number of surface-associated bacteria between two substrate types (filament vs. slide). Sequencing revealed microbial communities attached to artificial substrates in a hypereutrophic urban river were composed of 80,375 OTUs, and distributed in 47 phyla. Proteobacteria and Cyanobacteria/Chloroplast were the two dominant phyla, followed by Planctomycetes, Actinobacteria, Verrucomicrobia, Firmicutes and Bacteroidetes. Taxonomic composition showed ammonia-oxidizing microorganisms, fecal indicator bacteria and pathogens enriched in attached microbial communities, especially the ammonia-oxidizing Nitrosomonas bacteria. These results indicated that there were significant temporal and intra-river heterogeneity of attached microbial community structure, but no significant difference in community composition was detected between the two substrate types. [ABSTRACT FROM AUTHOR]