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A novel alphaproteobacterial strain JXJ CY 41T was isolated from a culture mass of Microcystis, collected from Lake Dianchi, south-west, China. Strain JXJ CY 41T was gram-strain-negative, aerobic, motile, with rod-shaped cells (0.4–1.0 × 1.7–3.5 μm). It was positive for catalase and starch hydrolysis, negative for oxidase and hydrolysis of Tweens (20, 40, and 80). Growth occurred at 10–44 °C, pH 5.0–10.0, and 0–5.0% (w/v) NaCl. Major fatty acids included C16:0 (28.1%), 11-methyl C18:1 ω7c (36.7%) and C18:1 ω7c (20.8%). Q10 was the sole ubiquinone. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, glycolipid, and an unidentified lipid. The DNA G + C content was 63.1%. Its 16S rRNA gene sequence showed high similarities with Devosia oryziradicis G19T (99.5%; not validly published), D. yakushimensis Yak96BT (98.3%) and D. ginsengisoli Gsoil 520T (98.1%), and less than 98.1% similarities with other members of the genus Devosia. The digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain JXJ CY 41T and its 5 closest similar strains were 19.9–24.1% and 75.7–80.5%, respectively. Based on the data above, strain JXJ CY 41T was identified as a novel species of the genus Devosia, for which the epithet Devosia lacusdianchii sp. nov. was proposed. The type strain is JXJ CY 41T (= KCTC 72812T = CGMCC 1.17502T). Strain JXJ CY 41T exhibited different interactions with Microcystis aeruginosa FACHB-905 (Maf) under different conditions, and Maf could control the bacterial cellular density by secreting unknown specific chemical compounds according to its nutritional requirements. [ABSTRACT FROM AUTHOR]

High-altitude pulmonary edema (HAPE) is a fatal threat for sojourners who ascend rapidly without sufficient acclimatization. Acclimatized sojourners and adapted natives are both insensitive to HAPE but have different physiological traits and molecular bases. In this study, based on GSE52209, the gene expression profiles of HAPE patients were compared with those of acclimatized sojourners and adapted natives, with the common and divergent differentially expressed genes (DEGs) and their hub genes identified, respectively. Bioinformatic methodologies for functional enrichment analysis, immune infiltration, diagnostic model construction, competing endogenous RNA (ceRNA) analysis and drug prediction were performed to detect potential biological functions and molecular mechanisms. Next, an array of in vivo experiments in a HAPE rat model and in vitro experiments in HUVECs were conducted to verify the results of the bioinformatic analysis. The enriched pathways of DEGs and immune landscapes for HAPE were significantly different between sojourners and natives, and the common DEGs were enriched mainly in the pathways of development and immunity. Nomograms revealed that the upregulation of TNF-α and downregulation of RPLP0 exhibited high diagnostic efficiency for HAPE in both sojourners and natives, which was further validated in the HAPE rat model. The addition of TNF-α and RPLP0 knockdown activated apoptosis signaling in endothelial cells (ECs) and enhanced endothelial permeability. In conclusion, TNF-α and RPLP0 are shared biomarkers and molecular bases for HAPE susceptibility during the acclimatization/adaptation/maladaptation processes in sojourners and natives, inspiring new ideas for predicting and treating HAPE. [ABSTRACT FROM AUTHOR]

An alpha-proteobacterial strain JXJ CY 53 T was isolated from the cyanosphere of Microcystis sp. FACHB-905 (MF-905) collected from Lake Dianchi, China. JXJ CY 53 T was observed to be an aerobic, Gram-stain-negative, oval shaped, and mucus-secreting bacterium. It had C18:1ω7c and C16:0 as the major cellular fatty acids, Q-10 as the predominant ubiquinone, and sphingoglycolipid, diphosphatidylglycerol, phosphatidylcholine, and phosphatidylmethylethanolamine as the polar lipids. The G + C content of DNA was 65.85%. The bacterium had 16S rRNA gene sequence identities of 98.9% and 98.7% with Sphingomonas panni DSM 15761 T and Sphingomonas hankookensis KCTC 22579 T, respectively, while less than 97.4% identities with other members of the genus. Further taxonomic analysis indicated that JXJ CY 53 T represented a new member of Sphingomonas, and the species epithet was proposed as Sphingomonas lacusdianchii sp. nov. (type strain JXJ CY 53 T = KCTC 72813 T = CGMCC 1.17657 T). JXJ CY 53 T promoted the growth of MF-905 by providing bio-available phosphorus and nitrogen, plant hormones, vitamins, and carotenoids. It could modulate the relative abundances of nonculturable bacteria associated with MF-905 and influence the interactions of MF-905 and other bacteria isolated from the cyanobacterium, in addition to microcystin production characteristics. Meanwhile, MF-905 could provide JXJ CY 53 T dissolved organic carbon for growth, and control the growth of JXJ CY 53 T by secreting specific chemicals other than microcystins. Overall, these results suggest that the interactions between Microcystis and its attached bacteria are complex and dynamic, and may influence the growth characteristics of the cyanobacterium. This study provided new ideas to understand the interactions between Microcystis and its attached bacteria. Key points: • A novel bacterium (JXJCY 53T) was isolated from the cyanosphere of Microcystis sp. FACHB-905 (MF-905) • JXJCY 53Tmodulated the growth and microcystin production of MF-905 • MF-905 could control the attached bacteria by specific chemicals other than microcystins (MCs) [ABSTRACT FROM AUTHOR]

Tobacco bacterial wilt caused by Ralstonia solanacearum often occurs under monocropping. Crop rotation significantly reduces disease by changing the microbial communities, both taxonomically and functionally, in the tobacco rhizosphere. In this study, tobacco rhizosphere soils were sampled from monocropping and tobacco-maize rotation fields. Based on metagenomic sequencing, measurements of soil properties, and the quantification of R. solanacearum, the results showed that rotation with maize increased the microbial diversity, complexity of microbial networks, and soil nutrient level in the tobacco rhizosphere and led to better tobacco growth. Tobacco rhizosphere microbes in monocropping fields were enriched for proteins related to pathogenicity and host infection processes. Moreover, microbes from the tobacco-maize rotation field had the strongest negative correlations with R. solanacearum. These microbes were mainly Actinobacteria, especially Solirubrobacter. Although the abundance of R. solanacearum did not significantly differ between monocropping and crop rotation fields, R.solanacearum did not cause outbreaks in tobacco-maize rotation fields, as there were no disease symptoms on tobacco. Based on structural equation modeling, we identified that general disease suppression had a stronger influence on R. solanacearum and tobacco performance than specific disease suppression. Moreover, general disease suppression may facilitate the establishment of specific disease suppression. This study revealed the functional changes in the rhizosphere microbiome and the mechanisms of disease suppression under tobacco-maize rotation. Our study further indicated that crop rotation could lead to the establishment of specific disease suppression in the longer term. [ABSTRACT FROM AUTHOR]

The world-class Jinchuan magmatic Ni-Cu-PGE (platinum-group element) sulfide deposit comprises four large orebodies (No. 1, 2, 3 and 24). Underground fan drilling discovered significant lateral extension of No. 2 orebody, referred as No. 2a in this study. From base to top, the No. 2a orebody comprises disseminated sulfide in olivine pyroxenites, net-textured ore in lherzolite, and massive ore. Despite different host rocks, the contents of Ni, Cu and PGE of the same types of sulfide ores from No. 2 and No. 2a orebodies are comparable. Mass balance calculation indicates that the parental magmas contained 0.01–0.05 ppb Ir and 0.2-0.8 ppb Pd, which are about one order of magnitude less than PGE abundances of undepleted continental flood basalts. PGE tenors (recalculated to 100% sulfides) of the net-textured ores from both orebodies increase upward. We attribute this to variations in magma:sulfide ratios of successive batches of recharged magmas and/or reaction of sulfides with less evolved magma. We propose that the No. 2a and No. 2 orebodies were located in the upstream and downstream parts of an originally sub-horizontal magma conduit, respectively. Sulfide liquids accumulated in the wider parts of the magma conduit to form No. 2a and No. 2 orebodies progressively. Variable locations within the intrusion and sharp contacts with other types of sulfide ore indicate that the massive ores formed by injection of pooled sulfide melt. Significant Pt-depletion of the massive ores and Pt enrichment in the adjacent net-textured ores suggest migration of residual fractionated sulfide liquids. [ABSTRACT FROM AUTHOR]

Extranodal natural killer/T-cell lymphoma (ENKTL) with hepatosplenic involvement is rare, accounting for approximately 0.2% of ENKTL cases. The clinicopathologic features of ENKTL with hepatosplenic involvement are still poorly understood. Seven cases of ENKTL with hepatosplenic involvement were investigated retrospectively by clinical features, pathology, immunophenotype, genotype, Epstein-Barr virus (EBV) status, and survival analysis. The median age was 36 years; three patients (3/7) had a history of primary nasal ENKTL. Six cases (6/7) presented liver or spleen structures that were replaced by neoplasms, and the neoplastic cells displayed diffuse infiltration; one case (1/7) displayed neoplastic cells scattered in hepatic sinuses and portal areas. The cellular morphology and immunohistochemical features were similar to those of ENKTL involving other sites. Follow-up data were available in five of the seven patients. All five patients received first-line chemotherapy based on L-asparaginase. Three patients died, and two were still alive by the last follow-up. The median overall survival (OS) was 21 months. ENKTL with hepatosplenic involvement is rare, regardless of whether it is initial or secondary. There are two histopathologic patterns of ENKTL with hepatosplenic involvement, and L-asparaginase-based chemotherapy combined with AHSCT might yield good efficacy. [ABSTRACT FROM AUTHOR]

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Magnetization in a ferromagnetic layer could be manipulated by the spin-orbit torque whose generation commonly relies on the spin-orbit coupling from the adjacent heavy-metal layer within the bilayer. The fact that the magnetic topological insulator possesses both the ferromagnetic order with perpendicular anisotropy and inherent spin-orbit coupling inspires to realize such a torque-induced magnetization switching without forming any heterostructure with other materials. Here, only using a single layer of magnetically-doped topological insulator Cr:(Bi,Sb)2Te3, we realize a magnetization switching only by applying a large dc current. Assisted by the magnetic history, such a switching behaves nonvolatile under zero field but becomes volatile otherwise, as consistently shown by magnetoelectric transports and magneto-optical Kerr effect measurements. Static and quasistatic current are found to be equivalent for the switching. We propose that this switching may associate with the torque resulted from the spin-orbit coupling and the compositional asymmetry in the Cr-profile of the single layer. Topological insulators (TIs), as a powerful reservoir of spin-orbit coupling, became popular to replace the heavy metals in bilayers to achieve magnetization switching with high efficiencies and low threshold current densities. By magnetically doping a single layer TI, the authors observe a zero-field magnetization of the TI that can be switched by dc current. [ABSTRACT FROM AUTHOR]

The quasi-1D chiral edge states in a quantum anomalous Hall insulator are dissipationless, while the 2D helical surface states in a topological insulator are insensitive to spin-independent scatterings due to the topological protection. Both serve as essential ingredients for topological electronics. Here, we integrate these states into a single device using selective area epitaxy based on the molecular beam epitaxy technique. The chiral edge state comes from the quantum anomalous Hall insulator Cr:(Bi,Sb)2Te3, while the helical surface state comes from the intrinsic topological insulator (Bi,Sb)2Te3 which only interfaces with a partial edge of the former, forming a selective-area heterostructure. At the heterointerface, the chiral state in Cr:(Bi,Sb)2Te3 is allowed to be scattered into (Bi,Sb)2Te3 so that the incoming current will be redistributed according to the coordination between the chirality and helicity. Our device enables the collaboration between chiral and helical states for low-dissipative transport with tunable current dimension. The quantum anomalous Hall effect is a transport phenomenon that has implications in the search for Majorana fermions and quantum metrology. Here, the authors prepare a quantum anomalous Hall bar composed of a magnetic/non-magnetic topological insulating selective-area heterostructure and observe a modulation of the chiral and helical transports at the interface between the two materials by transport measurements. [ABSTRACT FROM AUTHOR]

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The difficulty of releasing nutrients from soils in karst areas limits the yield of local crops and leads to poverty. In this study, two strains of plant growth-promoting rhizobacteria (PGPR) were isolated from the rhizosphere soil of typical plants in karst areas, which were both identified as Bacillus sp. and named GS1 and N1. And two isolates were used to construct a composite PGPR named MC1. These three strains of PGPR were used for soil inoculation in the pot experiment and field trial and their capacity to promote rice development was assessed. The results showed that MC1 inoculation exhibited notable rice growth-promoting ability in pot experiments, and, respectively, had an increment of 16.96, 18.74, and 11.50% in shoot biomass, total biomass, and rice height compared with control. This is largely attributed to PGPR's capacity to secrete phytohormones and soil enzymes, particularly urease (UE) in GS1, whose secreted UE content was significantly higher by 12.18% compared to the control. When applied to the field, MC1 inoculation not only increased rice yield by 8.52% and the available nutrient content in rice rhizosphere soil, such as available phosphorus (AP) and exchangeable magnesium (EMg); but also improved the abundance of beneficial rhizobacteria and the diversity of microbial communities in rice rhizosphere soil. Results in this study revealed that inoculated PGPR played a major role in promoting rice growth and development, and a new strategy for facilitating the growth of rice crops in agriculture was elucidated. Article Highlights: Two stains of Bacillus sp. isolated from the rhizosphere soil of typical plants in karst areas could promote rice growth and yield. PGPR exhibited the great potential of secreting phytohormones and soil enzymes. PGPR released the available nutrient for rice plants and alleviated the imbalance of nutrients in karst soils. Co-inoculation of PGPR could be a promising approach to improving crop yield and applied to agriculture production. [ABSTRACT FROM AUTHOR]

The osteonecrotic area of steroid-induced avascular necrosis of the femoral head (SANFH) is a hypoxic microenvironment that leads to apoptosis of transplanted bone marrow mesenchymal stem cells (BMSCs). However, the underlying mechanism remains unclear. Here, we explore the mechanism of hypoxic-induced apoptosis of BMSCs, and use the mechanism to improve the transplantation efficacy of BMSCs. Our results show that the long non-coding RNA AABR07053481 (LncAABR07053481) is downregulated in BMSCs and closely related to the degree of hypoxia. Overexpression of LncAABR07053481 could increase the survival rate of BMSCs. Further exploration of the downstream target gene indicates that LncAABR07053481 acts as a molecular "sponge" of miR-664-2-5p to relieve the silencing effect of miR-664-2-5p on the target gene Notch1. Importantly, the survival rate of BMSCs overexpressing LncAABR07053481 is significantly improved after transplantation, and the repair effect of BMSCs in the osteonecrotic area is also improved. This study reveal the mechanism by which LncAABR07053481 inhibits hypoxia-induced apoptosis of BMSCs by regulating the miR-664-2-5p/Notch1 pathway and its therapeutic effect on SANFH. Long non-coding RNA AABR07053481 is shown to inhibit hypoxia-induced apoptosis of bone marrow mesenchymal stem cells in rats by regulating the miR-664-2-5p/Notch1 pathway, promote the repair efficacy of BMSCs on early steroid-induced avascular necrosis of the femoral head. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Different acquisition data approaches have been used to fetch the fluorescence spectra. However, the comparison between them is rare. Also, the extendability of a sensor array, which can work with heavy metal ions and other types of analytes, is scarce. In this study, we used first- and second-order fluorescent data generated by 6-Aza-2-thiothymine-gold nanocluster (ATT-AuNCs) as a single probe along with machine learning to distinguish between a group of heavy metal ions. Moreover, the dimensionality reduction was carried out for the different acquisition data approaches. In our case, the accuracy of different machine learning algorithms using first-order data outperforms the second-order data before and after the dimensionality reduction. For proving the extendibility of this approach, four anions were used as an example. As expected, the same finding has been found. Furthermore, random forest (RF) showed more stable and accurate results than other models. Also, linear discriminant analysis (LDA) gave acceptable accuracy in the analysis of the high-dimensionality data. Accordingly, using LDA in high-dimensionality data (the first- and second-order data) analysis was highlighted for discrimination between the selected heavy metal ions in different concentrations and in different molar ratios, as well as in real samples. Also, the same method was applied for the anion's discrimination, and LDA gave an excellent separation ability. Moreover, LDA was able to differentiate between all the selected analytes with excellent separation ability. Additionally, the quantitative detection was considered using a wide concentration range of Cd2+, and the LOD was 60.40 nM. Therefore, we believe that our approach opens new avenues for linking analytical chemistry, especially sensor array chemistry, with machine learning. [ABSTRACT FROM AUTHOR]

AMPA receptors are tetrameric ionic glutamate receptors, which mediate 90% fast excitatory synaptic transmission induced by excitatory glutamate in the mammalian central nervous system through the activation or inactivation of ion channels. The alternation of synaptic AMPA receptor number and subtype is thought to be one of the primary mechanisms that involve in synaptic plasticity regulation and affect the functions in learning, memory, and cognition. The increasing of surface AMPARs enhances synaptic strength during long-term potentiation, whereas the decreasing of AMPARs weakens synaptic strength during the long-term depression. It is closely related to the AMPA receptor as well as its subunits assembly, trafficking, and degradation. The dysfunction of any step in these precise regulatory processes is likely to induce the disorder of synaptic transmission and loss of neurons, or even cause neuropsychiatric diseases ultimately. Therefore, it is useful to understand how AMPARs regulate synaptic plasticity and its role in related neuropsychiatric diseases via comprehending architecture and trafficking of the receptors. Here, we reviewed the progress in structure, expression, trafficking, and relationship with synaptic plasticity of AMPA receptor, especially in anxiety, depression, neurodegenerative disorders, and cerebral ischemia. [ABSTRACT FROM AUTHOR]

In this study, a new numerical model of ring shear tester for shear band soil of landslide was established. The special feature of this model is that it considers the mechanism of friction-induced thermal pressurization, which is potentially an important cause of high-speed catastrophic landslides. The key to the construction of this numerical ring shear model is to realize the THM (thermo-hydro-mechanical) dynamic coupling of soil particles, which includes the processes of frictional heating, thermal pressurization, and strength softening during shearing of solid particles. All of these are completed by using discrete element method. Based on this new model, the characteristics of shear stress change with shear displacement, as well as the variation of temperature and pore pressure in the specimen, are studied at shear rates of 0.055 m/s, 0.06 m/s, 0.109 m/s and 1.09 m/s, respectively. The results show that the peak strength and residual strength of specimen are significantly reduced when the mechanism of friction-induced thermal pressurization is considered. The greater the shear rate is, the higher the temperature as well as the pore pressure is. The effect of shear rate on the shear strength is bidirectional. The simulation results demonstrate that this model can effectively simulate the mechanism of friction-induced thermal pressurization of shear band soil during ring shear process, and the shear strength softening in the process. The new numerical ring shear model established in this study is of great significance for studying the dynamic mechanism of high-speed catastrophic landslides. [ABSTRACT FROM AUTHOR]

The Berezinskii-Kosterlitz-Thouless (BKT) transition is a topological transition driven by topological defects at a characteristic temperature, below which vortex-antivortex pairs bound and dissociate into free vortices above. Such transitions have been observed in superfluid helium films, superconducting films, quantum Hall systems, planar Josephson junction arrays, graphene, and frustrated magnets. Here we report the BKT-like transition in a quantum anomalous Hall insulator film. This system is a 2D ferromagnet with broken time-reversal symmetry, which results in quantized chiral/antichiral edge states around the boundaries of the magnetic domains/antidomains. The bindings and unbindings of these domain-antidomain pairs can take the roles played by vortex-antivortex pairs while the chirality takes over the vorticity, which drive the system to undergo the BKT-like transition. This multidomain network can be manipulated by coherent/competitive mechanisms like the applied dc current, perpendicular magnetic field, and temperature, the combination of which forms a line of critical points. The Berezinskii-Kosterlitz-Thouless topological phase transition has been observed in various systems, and involves vortex-antivortex pairs binding/un-binding. Here, such a transition is observed in a 2D ferromagnetic quantum anomalous Hall insulator film, revealed by temperature-dependent magneto-electrical transport measurements. [ABSTRACT FROM AUTHOR]

Since the first impoundment of the Three Gorges Reservoir (TGR) in China in 2003, more than 5000 landslides including potential landslides were identified. In this paper, a deep-seated active landslide in TGR area was analyzed. Fourteen years' monitoring data and field investigations from 2006 to 2020 were used to analyze the deformation characteristics, influencing factors, and meteohydrological thresholds. The landslide showed a none-overall periodic movement pattern featuring acceleration during long-duration rainfall and rapid transition to constant creep after rainfall events. Two secondary sliding masses, No. 1 and No. 2, were defined via field investigation. The reservoir has no impact on the deformation whereas long-duration-low-intensity rainfall is the main factor. At present, the cumulative displacements of the main sliding mass range from 0.9 to 3.2 m, and the deformation during the rainy season is gradually increasing. The boundary of this landslide was formed, and the boundary of No. 2 sliding mass became obvious. The probability of the failure of sliding mass No. 2 is very high under the conditions of continuous rainfall. The 15-day antecedent rainfall combined with 4-day cumulative rainfall could be the rainfall threshold which could be associated with the groundwater level S1 of 294 m above sea level for forecasting large deformation of Tanjiawan landslide. [ABSTRACT FROM AUTHOR]

In this study, the effects of different Sc + Zr compound addition on the tensile properties, impact toughness, stress corrosion cracking (SCC) properties, polarization curves, electrochemical impedance spectroscopy (EIS), and pitting corrosion (PC) of Al–Zn–Mg alloys are investigated. The results show that the Sc + Zr co-addition significantly inhibits the recrystallization behavior, refines the grain structure, and improves the tensile properties and impact toughness of the studied alloys. In fact, 0.43 wt% Sc + Zr-containing alloy achieves the maximum tensile properties, the tensile strength and yield strength are increased by 60.4 and 71.5 MPa, respectively. The impact toughness of 0.30 wt% Sc + Zr-containing alloy is 36.5 J/cm2, which is increased by 6.4 J/cm2. The Sc + Zr co-addition significantly reduces the SCC sensitivity, increases the charge transfer resistance, decreases the corrosion current density, and improves the PC resistance of Al–Zn–Mg alloys. The results of the strengthening model show that the main strength mechanism of Al–Zn–Mg alloys is precipitation strengthening of conventional η′ phases. The high toughness and corrosion resistance of alloys with Sc + Zr co-addition associated with the recrystallization resistance and the grain structures yielded by coherent Al3ScxZr1-x particles. [ABSTRACT FROM AUTHOR]

C-reactive protein (CRP), a non-specific acute-phase indicator of inflammation, has been widely recognized for its value in clinical diagnostic applications. With the advancement of testing technologies, there have been many reports on fast, simple, and reliable methods for CRP testing. Among these, the aptamer-based biosensors are the focus and hotspot of research for achieving high-sensitivity analysis of CRP. This review summarizes the progress of in vitro aptamer screening for CRP and the recent advances in aptamer-based CRP sensor applications, thus developing insight for the new CRP aptasensor design strategy. [ABSTRACT FROM AUTHOR]

This meta-analysis aimed to analyze retinal microvasculature features in eyes with Behçet's disease (BD) using optical coherence tomography angiography (OCTA). Electronic databases, including PubMed, Web of Science, Embase, and Cochrane Library, were comprehensively searched for published studies comparing retinal microvasculature characteristics between eyes with BD and controls. Continuous variables were calculated using the mean difference (MD) with 95% confidence interval (CI). Review Manager software (version 5.30) was used to conduct statistical analysis. A total of 13 eligible studies involving 599 eyes with BD and 622 control eyes were included in the meta-analysis. The pooled results showed that the macular whole enface superficial and deep vessel density (VD) values measured by OCTA were significantly lower in eyes with BD than in control eyes (superficial VD: MD = − 3.05, P < 0.00001; deep VD: MD = − 4.05, P = 0.0004). The foveal superficial and deep VD values were also significantly lower in the BD group than in the control group (superficial VD: MD = − 1.50, P = 0.009; deep VD: MD = − 4.25, − = 0.03). Similarly, the analysis revealed a significant reduction in the parafoveal superficial and deep VD in eyes with BD than in control eyes (superficial VD: MD = − 3.68, P < 0.00001; deep VD: MD = − 4.95, P = 0.0007). In addition, the superficial and deep foveal avascular zones (FAZs) were significantly larger in patients with BD than in controls (superficial FAZ: MD = 0.06, P = 0.02; deep FAZ: MD = 0.12, P = 0.03). The present meta-analysis found that macular whole enface VD, foveal VD, and parafoveal VD were lower in eyes with BD, and the FAZ was larger in patients with BD. The findings suggest that OCTA can assist clinicians in diagnosing and monitoring the status of patients with BD. [ABSTRACT FROM AUTHOR]

Drinking water treatment techniques are used globally in the context of water security and public health, yet they are not applicable to antibiotic resistance gene (ARG) contamination. Using high-throughput quantitative PCR, we analyzed the prevalence and diversity of ARGs and mobile genetic elements (MGEs) in water supplies. A total of 224 ARGs and MGEs were detected in all sampling sites. Absolute abundance and detected number of ARGs decreased significantly (P < 0.05) in sand filter water after drinking water treatment and increased thereafter at point-of-use (household tap water). Changes in the composition and diversity of the bacterial community were observed in water samples at different steps. A significant correlation (P < 0.001) between microbial communities and ARG profiles was observed, and variance in ARG profiles could be primarily attributed to community composition (11.9%), and interaction between community composition, environmental factors and MGEs (30.7%). A network analysis was performed, and the results showed eight bacterial phyla were significantly correlated with nine different classes of ARGs, suggesting the potential bacterial host for ARGs. This study suggested that although the absolute abundance of ARGs decreased after treatment of drinking water treatment plants (DWTPs), the rebounded of ARGs in the water distribution system should not be neglected. [ABSTRACT FROM AUTHOR]

Igneous rocks can provide important insights into geodynamic evolution of orogenic belts. During the Paleozoic to early Mesozoic, the East Kunlun Orogenic Belt (EKOB) had experienced the evolution of Proto-Tethys and Paleo-Tethys Oceans successively. However, the precise ages of occurrence of specific geodynamic processes are still unclear. Here, we study the crystallization age and petrogenesis of Paleozoic to early Mesozoic intrusive rocks in the Eastern Kunlun Orogenic Belt (EKOB) to constrain regional geodynamic evolution. These intrusive rocks are located in the Paleozoic to early Mesozoic magmatic arc, which is parallel to the Tethys ophiolite belt. 440 Ma BDG (Baidungou) diorite and 430 Ma LTG (Luotuogou) granodiorite porphyry are probably derived from mixing-assimilation-storage-homogenization (MASH) zone in the lower crust and show significant depletions in high field strength elements (HFSEs, Nb, Ta, Ti) with characteristics of arc magmatic rocks. The 414 Ma LTG granite porphyry shows the geochemical characteristics of A2-type granites and was emplaced in an extensional setting. Permian to Triassic mafic dike swarm show low contents of SiO2 and high MgO contents, combined with their depletions in HFSEs and enrichments in large ion lithophile elements (LILEs), it is concluded that they are derived from subduction-related fluid metasomatized mantle (SFMM). 247 Ma XSG granites display SiO2 contents varying from 68.06 to 70.67 wt. % with high Rb/Sr (0.12–0.30), Th/Nb (1.25–1.38), but low Nb/Ta (9.1–13.0) ratios, which is similar to bulk continental crust. All the samples of XSG granites show (La/Yb)N ratios of 10.3–10.6 without adakitic affinity suggesting that they are derived from lower crust with normal thickness. Combined with previous research, it is suggested that the EKOB experienced two Wilson cycles during Paleozoic to early Mesozoic and the Paleo-Tethys Ocean reopened at Carboniferous after the Proto-Tethys Ocean was completely closed at late Silurian. Orogenic magmatism in the EKOB shows episodic characteristics and can be further divided into ten episodes (E1, E2, E3, E4, E5, E6, E7, E8, E9, and E10) corresponding to ten different geodynamic regimes. [ABSTRACT FROM AUTHOR]

In the past few decades, due to the rapid development of industry and the rapid growth of population, emissions of pollutants to the environment have increased dramatically, and the demand for drinking water is also increasing. Water treatment is a matter of concern because it is directly related to the health of humans and wildlife. Graphene and its derivatives have potential applications in seawater desalination and wastewater treatment due to their unique pore structure and ionic molecular sieving separation capabilities. Graphene, graphene oxide (GO), and reduced graphene oxide (rGO) can be formulated into nanoporous materials and composites with tunable properties that can be optimized for water filtration. Methods for perforating graphene include ion etching/ion bombardment and electron beam nanometer engraving, which are briefly introduced in this paper. Graphene-based composites further expand the capabilities of graphene in seawater desalination and wastewater treatment, by introducing new features and properties. In this review, the performance improvement of graphene-based separation membranes in decontamination and desalination in recent years is reviewed in detail. This review focuses on improving the performance of graphene-based membranes for separation, decontamination, and seawater desalination applications, by discussing how various modifications and preparation methods impact important performance properties, including water permeance, selectivity, rejection of solutes, membrane mechanical strength, and antifouling characteristics. We also discuss the outlook for future development of graphene-based membranes. [ABSTRACT FROM AUTHOR]

Small sample size (SSS) problems pose a tremendous challenge in modeling tasks due to insufficient training samples, especially in process industry where thousands of useless samples overwhelm very limited valuable samples, leading to deterioration on the prediction ability of trained models for key variables. In this study, the prediction ability to forecast models is enhanced by generating virtual samples. Considering the integrated effects of attributes, a new data augment approach, called ITNN-VSG, which integrates virtual sample generation (VSG) with input-training neural network (ITNN), was put forward to enlarge training datasets for improving the performance of forecasting models. In the absence of any available domain-specific knowledge about target models, a query-driven interpolation process was first developed to explore the overall tendency of data distribution in both sparse regions and dense regions. Second, an ITNN with fixed weights was used to calculate the input corresponding to the virtual output generated by the interpolation process. To validate the effectiveness of the proposed approach, several in silico experiments were carried out on a benchmark dataset from sinc(x) function, followed by a real-world application to purified terephthalic acid (PTA) solvent system. The experimental results demonstrated that the proposed approach outperformed other existing approaches such as mega-trend-diffusion and tree-based-trend-diffusion. [ABSTRACT FROM AUTHOR]

It is of critical importance for our understanding of speciation process to determine the forms of reproductive isolation and their relative importance in species divergence. Oryza nivara and O. rufipogon are direct ancestors of Asian cultivated rice and a progenitor-daughter species pair. Investigating the reproductive isolation between them provides insights into plant speciation and helps understanding of the rice domestication. Here, we quantitatively measured the major components of reproductive isolation between the two species based on common garden and crossing experiments for three pairs of sympatric populations in Nepal, Cambodia and Laos. We revealed significant differences in the flowering times between species pairs, with O. nivara flowering much earlier than O. rufipogon. A very weak reduction in seed set but no reduction in F1 viability and fertility were detected for the crosses between species relative to those within species. Moreover, we detected asymmetrical compatibility between species and found that emasculation significantly decreased pollination success in O. nivara but not in O. rufipogon. Our study demonstrates that the divergence between O. nivara and O. rufipogon is maintained almost entirely by the difference in flowering times and suggests that differential flowering times contribute to both habitat preferences and reproductive isolation between species. [ABSTRACT FROM AUTHOR]

To study the creep characteristics of mudstone under disturbed load, creep rock triaxial compression disturbance tests under different disturbance amplitudes and frequencies are conducted using a self-made triaxial disturbed creep test bench for rock. The influence of different factors on the creep deformation law of each stage is analyzed. The results show that the disturbance effect has a significant impact on the creep properties of mudstone, and various factors have different effects on the creep stages. The instantaneous deformation variable, creep decay time, and steady creep rate change exponentially with the increase in axial pressure, and increase linearly with the increase in disturbance amplitude and disturbance frequency. The disturbance amplitude has a more significant effect on the instantaneous deformation, steady-state creep rate, and accelerated creep. According to the analysis of the test results, a nonlinear disturbance creep damage model based on Burger's model is established. The model is identified and calculated by the improved least squares method based on pattern search. The influence of different disturbance factors on the creep parameters is analyzed. The model fitting results and experimental results are compared to demonstrate that the model is used to simulate different disturbances. It was observed that rock creep under certain conditions exhibits certain adaptability. It is of great significance to carry out rock disturbance creep experiments and study the theory of disturbance creep to ensure the long-term stability of deep rock mass in complex environment. [ABSTRACT FROM AUTHOR]

Objective: To observe the effect and molecular mechanism of ethyl acetate extract of Sceptridium ternatum (STE) on the monocrotaline (MCT)-induced pulmonary arterial hypertension (PAH). Methods: The main chemical components of Sceptridium ternatum were determined, and the effects in PAH rats were observed. A total of 140 Sprague Dawley rats were randomly and equally divided into the normal group, the model group, the Bosentan group, and the STE groups (2.5, 5, 10 g/kg) by the random number table method. The characteristic indicators of PAH were measured, and immunohistochemistry was used to observe the lung tissue of rats. Morphological changes of the lung tissue were observed under the light microscope. Results: Compared with the normal group, rats in the model group showed a significant increase in right ventricular free wall thickness (RVFWT), mean pulmonary arterial pressure (mPAP), mean right ventricular pressure (mRVP), max right ventricular pressure (max RVP), weight of right ventricle (RV), and lung index (LI), while a significant decrease in pulmonary artery acceleration time (PAAT, P<0.01). Compared with the model group, rats treated with STE had a significant decrease of RVFWT, mPAP, mRVP, max RVP, and RV, while a significant increase of PAAT (P<0.01). After injection of MCT, nuclear factor- κB (NF- κB) p65 and α -smooth muscle actin (α -SMA) expression levels were up-regulated, and on the contrary, the treatment groups showed a significant down-regulation without dose-dependent trend. Conclusions: STE can relieve the PAH in rats. STE may relieve pulmonary vascular disease and pulmonary injury by down-regulating the expression of NF- κB p65 and α -SMA. [ABSTRACT FROM AUTHOR]

Purpose: The discovery of comammox Nitrospira being capable of complete oxidising ammonia to nitrate radically challenged the conventional concept of two-step nitrification. However, the response of comammox Nitrospira to nitrification inhibitors (NIs) and their role in soil nitrification remain largely unknown, which has hindered our ability to predict the efficiency of NIs in agroecosystems. Materials and methods: We evaluated the effect of four NIs, 2-chloro-6-(trichloromethyl) pyridine (nitrapyrin), 3,4-dimethylpyrazole phosphate (DMPP), allylthiourea (ATU) and dicyandiamide (DCD) on the growth of comammox Nitrospira, ammonia-oxidising archaea (AOA) and ammonia-oxidising bacteria (AOB) in two pasture and arable soils. Results and discussion: The amendment of nitrogen fertiliser significantly increased soil nitrate concentrations over time, indicating a sustaining nitrification activity in both soils. The addition of all the four NIs effectively reduced the production of nitrate in both soils, but to varying degrees during incubation. The abundances of comammox Nitrospira clade A were significantly increased by addition of nitrogen fertilisers and significantly impeded by the four NIs in the pasture soil, but their abundances were only remarkably hindered by nitrapyrin in the arable soil. All the four NIs obviously inhibited the AOB abundances in both soils. Except for DMPP, the other three NIs effectively suppressed the AOA abundances in both soils. Conclusions: We provided new evidence that growth of comammox Nitrospira clade A can be stimulated by nitrogen fertilisers and inhibited by various nitrification inhibitors, suggesting their potential role in nitrification of agricultural soils. [ABSTRACT FROM AUTHOR]

An ultra-sensitive method is described here for the determination of HIF-1α (an early biomarker for myocardial infarction) in circulating exosomes in serum. Gold nanospheres were functionalized with a HIF-1α-binding aptamer via sulfydryl chemistry. The apt-AuNP-coated gold seeds were grown by seed-mediated growth, and this significantly increased the peroxidase-mimicking property the nanoparticles. A chromogenic system composed of 3,3′5,5′-tetramethylbenzidine and hydrogen peroxide was used. Absorbance at 652 nm increases linearly in the 0.3 to 200 ng L−1 HIF-1α concentration range, and the limit of detection is 0.2 ng L−1. The method was tested by analyzing rat serum from isoproterenol (ISO)-induced myocardial infarction. It allows HIF-1α to be directly determined in a 25 μL sample without preconcentration. The assay is not interfered by the polydispersity of exosomes released under either health and disease conditions. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Central South University is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, the effects of three types of commonly used adhesives were studied via experiment and simulation. The results show that the strain sensitivity of fiber Bragg grating (FBG) sensor is about 1.201 pm/με and the effects of three adhesives of epoxy resin, AB glue and 502 glue with the same thickness and length on sensitivity coefficients of FBG sensors are 99.20%, 93.80% and 96.50%, respectively. Finally, the sensitivity coefficient of the simulated FBG sensor is the same as the test result by ANSYS modeling. [ABSTRACT FROM AUTHOR]

Methylation of cytosine to 5-methylcytosine (5mC) is a prevalent DNA modification found in many organisms. Sequential oxidation of 5mC by ten-eleven translocation (TET) dioxygenases results in a cascade of additional epigenetic marks and promotes demethylation of DNA in mammals1,2. However, the enzymatic activity and function of TET homologues in other eukaryotes remains largely unexplored. Here we show that the green alga Chlamydomonas reinhardtii contains a 5mC-modifying enzyme (CMD1) that is a TET homologue and catalyses the conjugation of a glyceryl moiety to the methyl group of 5mC through a carbon–carbon bond, resulting in two stereoisomeric nucleobase products. The catalytic activity of CMD1 requires Fe(ii) and the integrity of its binding motif His-X-Asp, which is conserved in Fe-dependent dioxygenases3. However, unlike previously described TET enzymes, which use 2-oxoglutarate as a co-substrate4, CMD1 uses l-ascorbic acid (vitamin C) as an essential co-substrate. Vitamin C donates the glyceryl moiety to 5mC with concurrent formation of glyoxylic acid and CO2. The vitamin-C-derived DNA modification is present in the genome of wild-type C. reinhardtii but at a substantially lower level in a CMD1 mutant strain. The fitness of CMD1 mutant cells during exposure to high light levels is reduced. LHCSR3, a gene that is critical for the protection of C. reinhardtii from photo-oxidative damage under high light conditions, is hypermethylated and downregulated in CMD1 mutant cells compared to wild-type cells, causing a reduced capacity for photoprotective non-photochemical quenching. Our study thus identifies a eukaryotic DNA base modification that is catalysed by a divergent TET homologue and unexpectedly derived from vitamin C, and describes its role as a potential epigenetic mark that may counteract DNA methylation in the regulation of photosynthesis. An algal TET dioxygenase homologue, CMD1, uses vitamin C as a glycerol donor to modify 5-methylcytosine and helps to regulate gene transcription in response to high light levels. [ABSTRACT FROM AUTHOR]

In this paper, the 3D drawing software UG is used to establish the geometric modeling of T tube for hydroforming process, and the software DYNAFORM is used to simulate the forming performance of T-shaped tube under different loading paths to obtain the simulation value of forming performance parameters. Next, the response surface method is used to analyze the influence of the main factors on hydroforming formability. The loading path, including axial feeding, internal pressure, and backward displacement, and friction coefficient are included in the main factors; the minimum thickness value, the height of branch tube, and the radius of limiting circle angle are considered as important characteristics that govern the forming performance. According to the optimization evaluation criteria, the perturbation plots and the interaction effect of different test factors, the main factors are optimized, and the best value of loading path was selected. Finally, the comparison of simulation and experiment under the optimal loading path shows that the error between experiment and simulation is within 5%, indicating that the loading path optimization method has high accuracy and good feasibility. [ABSTRACT FROM AUTHOR]

Background and Objectives: Astragaloside IV (AGS IV) is the most important bioactive constituent of Radix Astragali. However, its disappointing clinical application is mainly caused by its very low solubility in biologic fluids, resulting in poor bioavailability after oral administration. We recently obtained a novel water-soluble derivative of AGS IV (astragalosidic acid, LS-102) that displayed significant cardioprotective potential against hypoxia-induced injury. The objective of this study was to investigate the intestinal absorption, main pharmacokinetic parameters and acute toxicity of LS-102 in rodents compared with AGS IV.Methods: An oral dose of LS-102 and AGS IV (20 mg/kg) was administered to Sprague-Dawley (SD) rats, and blood samples were collected at predetermined time points. The plasma concentrations were detected by a validated UHPLC-MS/MS method, and pharmacokinetic parameters were calculated using a compartmental model. In the intestinal permeability study, the transport of LS-102 across Caco-2 cell monolayers was investigated at six concentrations from 6.25 to 250 µM. Moreover, the acute toxicity of LS-102 (40-5000 mg/kg) via a single oral administration was investigated in BALB/c mice.Results: LS-102 was rapidly absorbed, attaining a maximum concentration of 248.7 ± 22.0 ng/ml at 1.0 ± 0.5  h after oral administration. The relative bioavailability of LS-102 was twice that of AGS IV. LS-102 had a Papp (mean) of 15.72-25.50 × 10−6 cm/s, which was almost 500-fold higher than that of AGS IV, showing that LS-102 had better transepithelial permeability and could be better absorbed in the intestinal tract. The acute toxicity study showed no abnormal changes or mortality in mice treated with LS-102 even at the single high dose of 5000 mg/kg body weight.Conclusions: Oral LS-102 produced a pharmacokinetic profile different from AGS IV with higher bioavailability, while the toxic tolerance was similar to previous estimates. Thus, we speculated that LS-102 might provide better clinical efficacy and be a potential candidate for the new drug development of Radix Astragali. [ABSTRACT FROM AUTHOR]

The NAC transcription factor (TF) plays a pivotal role in resisting various abiotic stresses, and it has been proved that the overexpression of NAC transcription factors (TFs) in Arabidopsis is beneficial to increase drought tolerance. However, the function of NAC genes in chrysanthemum remains unclear. Here, we conducted physiological and molecular experiments to assess the role of DgNAC1 in response to drought stress of chrysanthemum. DgNAC1-overexpressed chrysanthemum was significantly more drought-resistant than wild type (WT). Especially, the transgenic chrysanthemum presented a greater survival rates (86.42, 88.89 and 87.65%, respectively) than WT (41.98%) under drought conditions. It also showed higher leaf water potential and relative water content; lower relative electrolyte conductivity; fewer accumulations of malondialdehyde, hydrogen peroxide (H2O2), superoxide anion (O2−); higher activities of superoxide dismutase, peroxidase, catalase; and more content of proline, chlorophyll, soluble protein, soluble sugar, glutathione (GSH), glutathione disulphide (GSSG), as well as higher ratio of GSH/GSSG than those of WT during drought stress. Moreover, stress-responsive genes in transgenic chrysanthemum showed a significant up-regulation than in WT under drought stress. Therefore, all the above results suggested that DgNAC1 served as an active regulator in chrysanthemum’s responses to drought stress, and it may have a significant impact on the molecular breeding of drought-resistant plants as well. [ABSTRACT FROM AUTHOR]

Magnetic insulators (MIs) attract tremendous interest for spintronic applications due to low Gilbert damping and the absence of Ohmic loss. Spin-orbit torques (SOTs) on MIs are more intriguing than magnetic metals since SOTs cannot be transferred to MIs through direct injection of electron spins. Understanding of SOTs on MIs remains elusive, especially how SOTs scale with the MI film thickness. Here, we observe the critical role of dimensionality on the SOT efficiency by studying the MI layer thickness-dependent SOT efficiency in tungsten/ thulium iron garnet (W/TmIG) bilayers. We show that the TmIG thin film evolves from twodimensional to three-dimensional magnetic phase transitions as the thickness increases. We report the significant enhancement of the measured SOT efficiency as the TmIG thickness increases, which is attributed to the increase of the magnetic moment density. We demonstrate the current-induced SOT switching in the W/TmIG bilayers with a TmIG thickness up to 15 nm. [ABSTRACT FROM AUTHOR]

Geometric Hall effect is induced by the emergent gauge field experienced by the carriers adiabatically passing through certain real-space topological spin textures, which is a probe to non-trivial spin textures, such as magnetic skyrmions. We report experimental indications of spin-texture topological charges induced in heterostructures of a topological insulator (Bi, Sb)2Te3 coupled to an antiferromagnet MnTe. Through a seeding effect, the pinned spins at the interface leads to a tunable modification of the averaged real-space topological charge. This effect experimentally manifests as a modification of the field-dependent geometric Hall effect when the system is field-cooled along different directions. This heterostructure represents a platform for manipulating magnetic topological transitions using anti- ferromagnetic order. [ABSTRACT FROM AUTHOR]

Autoantibodies against poly-U-binding factor 60 kDa protein (PUF60) have been reported in Caucasian dermatomyositis (DM) patients. However, their clinical significance in idiopathic inflammatory myopathy (IIM) remains to be fully clarified. Our objective was to analyze the prevalence and clinical significance of anti-PUF60 antibodies in a large cohort of Chinese IIM patients. In our study, 388 IIM patients, 301 disease controls, and 167 healthy controls (HCs) were involved. An enzyme-linked immunosorbent assay (ELISA) was developed to detect serum anti-PUF60 levels and was validated using immunoblotting methods. Unpaired Mann-Whitney U test and Spearman correlation analysis were used when appropriate. Anti-PUF60 antibodies were observed in IIM patients at a frequency of 10.6% (41/388). Subgrouping analysis revealed that the prevalence of anti-PUF60 antibodies was 10% in DM, 5.5% in polymyositis (PM), 10% in immune-mediated necrotizing myositis (IMNM), and 26.5% in myositis-overlap syndrome. Anti-PUF60 antibodies were also observed in systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), and Sjögren’s syndrome (SS) patients at a positive rate of 17.3, 14.5, and 10.1% respectively. Intriguingly, anti-PUF60 antibodies were frequently observed in clinically amyopathic dermatomyositis (CADM) patients and DM patients without currently known myositis autoantibodies. Furthermore, DM patients with anti-PUF60 antibodies had higher prevalence of skin ulcerations. Moreover, longitudinal investigation in eight DM patients with anti-PUF60 antibodies revealed that the antibodies levels decreased with disease remission. Anti-PUF60 antibodies were nonspecific for myositis, since they could be detected in other rheumatic diseases. Further investigation of anti-PUF60 antibodies may reveal shared pathogenic pathways in systemic autoimmune disorders. [ABSTRACT FROM AUTHOR]

The effect of an ultrasonic field on the microstructure and mechanical properties of 7085 aluminum alloy during solidification was investigated by optical microscopy, Vickers hardness test, tensile test, scanning electron microscopy (SEM) with energy dispersive X-ray spectrometry, and electron probe micro-analysis (EPMA). The results showed that the grains of aluminum alloy were significantly refined and secondary phases were dispersed and distributed uniformly at the grain boundaries, due to ultrasonic treatment (UST). By EPMA, it was observed that the distribution of the main elements Al, Zn, Mg and Cu was more homogeneous in alloys with UST, than in alloys without UST. The mechanical properties of the aluminum alloy also significantly improved. As demonstrated by the SEM fractography of the fractured faces of several castings, fracture of the unrefined specimens occurred in a brittle manner, whereas the cracks of the refined specimens showed quasi-cleavage fracture. [ABSTRACT FROM AUTHOR]

Al-Zn-Mg-Sc-Zr alloy samples were annealed to four different states (under-aging, peak-aging, over-aging and double-aging) and then thoroughly investigated by means of electron backscatter diffraction (EBSD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), tensile and fatigue crack growth rate tests to explore the influence of annealing treatment on microstructure and fatigue crack growth behavior. The results indicate that Al3(Sc,Zr) particles can effectively refine grains and enhance tensile properties and fatigue properties. After annealing treatment, the under-aged sample and double-aged sample obtained average grain sizes of 4.9473 and 4.1257 μm, and the maximum value of yield/tensile strength (561 MPa/581 MPa) was obtained in peak-aged state. In the Paris region, fatigue crack growth rate, crack deflection and bifurcation, crack blunting and inter/trans-granular propagation were discussed based on data fitting and Laird model and Griffith theory. And the results show that the under-aged sample possesses the best resistance to fatigue crack propagation and the most tortuous and bifurcated crack path. For all samples, the fatigue crack growth rate in the rupture region was inversely proportional to yield strength. [ABSTRACT FROM AUTHOR]

The microstructural evolution of 2026 aluminum alloy during homogenization treatment was investigated by optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDS), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The results show that severe dendritic segregation exists in the as-cast 2026 alloy and the main secondary phases at grain boundary are S (Al2CuMg) and θ (Al2Cu) phases. Elements Cu, Mg and Mn distribute unevenly from grain boundary to the inside of as-cast alloy. With the increase of homogenization temperature or the prolongation of holding time, the residual phases gradually dissolve into the matrix α(Al) and all the elements become more homogenized. According to the results of microstructural evolution, differential scanning calorimetry and X-ray diffraction, the optimum homogenization parameter is at 490 °C for 24 h, which is consistent with the result of homogenization kinetic analysis. [ABSTRACT FROM AUTHOR]