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An increasing number of geological hazards along high-speed railways on the Qinghai–Tibetan Plateau have occurred and have resulted in a profound influence on old infrastructure, which has attracted increasing attention. The landslide event that occurred on September 15, 2022, in Jiujiawan village, Xining city, Qinghai Province, is a typical case. Based on field investigations and remote sensing interpretations, a comprehensive analysis was conducted on the landslide. Additionally, the potential secondary failure of the current Jiujiawan landslide was assessed using Fast Lagrangian Analysis of Continua in Three Dimensions (FLAC3D). Based on the application of the small baseline subset-interferometric synthetic aperture radar (SBAS-InSAR) technique to SAR images from February 24, 2017 to September 14, 2022, a significant westward horizontal deformation was found to have been formed prior to the occurrence of the landslide. The maximum annual average deformation rate in the line of sight (LOS) direction reached −45 mm/yr, with a maximum cumulative deformation of −178 mm. This value was consistent with the continual increase in annual precipitation (2.51 mm/yr) prior to the occurrence of the landslide. The accumulated precipitation before the landslide was 279.8 mm, accounting for 54.2% of the total annual precipitation, with a particularly notable surge in monthly precipitation observed during August (250.3 mm). Additionally, the occurrence of a seismic event with a magnitude of Ms 6.9 in Menyuan County, 80 km away from Xining, could be a potential triggering factor to the landslide, as evidenced by an abrupt subsidence alteration observed prior to and following the earthquake. The maximum subsidence in the line of sight (LOS) direction exceeded 11 mm, exhibiting a highly consistent spatial distribution with the occurrence range of landslides. These results suggest that the Jiujiawan landslide was likely induced by earthquake events in the early stage and heavy rainfall in the later stage. The FLAC3D numerical simulation show that after the landslide, the slope remained marginally stable under natural conditions; however, it is susceptible to reactivation with heavy rainfall. [ABSTRACT FROM AUTHOR]

Background: Cataract contributes to visual impairment worldwide, and diabetes mellitus accelerates the formation and progression of cataract. Here we found that the expression level of miR-204-5p was diminished in the lens epithelium with anterior lens capsule of cataract patients compared to normal donors, and decreased more obviously in those of diabetic cataract (DC) patients. However, the contribution and mechanism of miR-204-5p during DC development remain elusive. Methods and result: The mitochondrial membrane potential (MMP) was reduced in the lens epithelium with anterior lens capsule of DC patients and the H2O2-induced human lens epithelial cell (HLEC) cataract model, suggesting impaired mitochondrial functional capacity. Consistently, miR-204-5p knockdown by the specific inhibitor also attenuated the MMP in HLECs. Using bioinformatics and a luciferase assay, further by immunofluorescence staining and Western blot, we identified IGFBP5, an insulin-like growth factor binding protein, as a direct target of miR-204-5p in HLECs. IGFBP5 expression was upregulated in the lens epithelium with anterior lens capsule of DC patients and in the HLEC cataract model, and IGFBP5 knockdown could reverse the mitochondrial dysfunction in the HLEC cataract model. Conclusions: Our results demonstrate that miR-204-5p maintains mitochondrial functional integrity through repressing IGFBP5, and reveal IGFBP5 may be a new therapeutic target and prognostic factor for DC. [ABSTRACT FROM AUTHOR]

In practical applications, some sparse signals have structural characteristics of block sparsity. Under the hypothesis of removing the requirements on the noise in recent literature concerning the ℓ 2 / ℓ p (0 < p ≤ 1) minimization method, uniform block restricted isometry property (B-RIP) condition is established for the stable recovery of approximately block k-sparse signals with partial block support information by employing the weighted ℓ 2 / ℓ p minimization method. Compared with the state-of-the-art results, the newly-obtained results present more relaxed sufficient condition for block sparse signal recovery, and meanwhile provide more precise reconstruction error estimations in different noise settings. Numerical experiments demonstrate that the new method exhibits a substantial increase in the reconstruction quality for highly undersampled block structural signals. [ABSTRACT FROM AUTHOR]

In recent years, lakes on the Qinghai–Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai–Tibet Highway, Qinghai–Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai–Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel–1 satellite image data and small baseline subset interferometry synthetic aperture radar (SBAS–InSAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array–type L–band synthetic aperture radar (ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar (D–InSAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight (LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai–Tibet Highway and Qinghai–Tibet Railway. [ABSTRACT FROM AUTHOR]

A zero-valent iron-loaded corn straw char (ZVI-CSC) was synthesized in this study for the remediation of As(V) and Cd(II) contamination. The impact of ZVI-CSC on the adsorption performance of As(V) and Cd(II) in solution, as well as their migration properties in soil, was investigated through adsorption kinetics and soil column leaching experiments, respectively. The results showed that the adsorption capacity of As(V) by ZVI-CSC was significantly improved to 14.42 g·kg−1 at pH = 3, compared with unmodified corn straw char (CSC). However, the adsorption capacity of Cd(II) was not improved. In the leaching experiments, the addition of ZVI-CSC to As(V)-contaminated soil resulted in a significant reduction of cumulative As(V) release rate from 32.26 to 3.11%, compared with corn straw char (CSC). Moreover, the role of ZVI in As(V)/Cd(II) remediation was analyzed. nZVI forms ≡Fe-OH and ≡Fe-OOH due to oxidation, which can form monodentate and bidentate complexes with As(V) via ligand exchange, thus promoting As immobilization. Furthermore, to further improve the adsorption performance of Cd(II), the electrostatic potential (ESP) of biochars with different surface functional groups (C = O, C–O–C, –OH, and –COOH) and their bond dissociation enthalpy (BDE) with As(V) and Cd(II) were calculated based on density functional theory (DFT). The results showed that –OH was the most effective for As(V) adsorption, and C–O–C was the most effective for Cd(II) adsorption. C = O and –COOH can be used to the simultaneous adsorption of As(V) and Cd(II). Therefore, the surface functional groups of ZVI-CSC can be selectively modified to improve its adsorption performance of As(V) and Cd(II). [ABSTRACT FROM AUTHOR]

The cryptochrome/photolyase family (CPF) is an extensively distributed and highly conserved gene family. These include photolyases, which repair UV (Ultraviolet) induced DNA damage, and cryptochromes, which serve as blue-light receptors in terrestrial plants. This study focused on the CPF members of the economically valuable brown alga Saccharina japonica and traced the evolutionary relationships and distribution of CPF members in a variety of algae. Six distinct CPF members were discovered in the genomes of S. japonica and Undaria pinnatifida. For the phylogenetic analysis, 94 CPF members were collected and identified from 24 additional different species. The phylogenetic analysis disclosed that the CPF family consisted of five main branches. It is worth mentioning that CPF members of Ectocarpus siliculosus and U. pinnatifida consisted of two types that evolved from both (6–4) pyrimidine-pyrimidone adduct [(6–4) photoproduct] photolyase [(6–4) photolyase] and cyclobutane pyrimidine dimer type II (CPD type II) photolyase. The members of the CPF identified in S. japonica evolved exclusively from CPD type II photolyase. The Sj Cryptochrome-DASH1 (CRY-DASH1) and Sj CPD genes have distinctly differential expression patterns under various light quality conditions. Protein–protein interactions may be utilized by Sj CPF members to regulate downstream Timeless genes. Nonetheless, this requires additional experimental confirmation. These findings shed new light on the functional and regulatory pathways of CPFs in algae. [ABSTRACT FROM AUTHOR]

Inconel 718 (IN718) superalloy is extensively used in various applications owing to its excellent comprehensive property. Fabricating Inconel 718 (IN718) superalloy by selective laser melting holds great promise for producing complex aerostructure components. In this work, the influence of scanning strategies, laser power, scanning speed and hatch distance were revealed and compared. Further, different solution treatments at various temperatures for 1 h followed by a two-step aging at 720/620 °C were employed to improve the mechanical properties of as-built IN718 alloy. The microstructure, hardness and tensile behavior of the as-built and heat-treated samples were investigated, respectively. Results showed that designing scanning strategies by changing rotation angle between scanning tracks had a limited impact on the relative density of samples while influencing the hardness of the samples. The microstructure of the as-built IN718 was a mixture of columnar and equiaxial grains with γ matrix and Laves phase precipitates in the grain boundaries. After heat treatment, the columnar structure was converted into equiaxial grains, weakening the anisotropy in samples. Meanwhile, the dissolution of Laves phase and formation of fine γ′ and γ″ precipitates dispersively distributed in the matrix became more remarkable with increasing solution temperature. As a result, when solution-treated at 1000 °C, the hardness and tensile strength reached 450.52 HV and 1396.22 MPa, respectively, and such values were increased by 28.7 and 26.9% in comparison with the AMS 5662. [ABSTRACT FROM AUTHOR]

Through interface engineering and content control strategy, a PdBi bimetallic interface structure was constructed for the first time to selectively convert CO2 to formate with a remarkably high Faraday efficiency (FEformate) of 94% and a partial current density (jformate) of 34 mA·cm−2 at −0.8 V vs. reversible hydrogen electrode (RHE) in an H-cell. Moreover, the PdBi interface electrocatalyst even exhibited a high current density of 180 mA·cm−2 with formate selectivity up to 92% in a flow cell and could steadily operate for at least 20 h. Electrochemical in-situ attenuated total reflection surface enhanced infrared absorption spectroscopy (ATR-SEIRAS) confirmed that the PdBi interface could greatly weaken the adsorption of *CO intermediates due to electronic and geometric effects. Density functional theory (DFT) calculations also established that the PdBi interface regulated the CO2-to-formate pathway by reducing the energy barrier toward HCOOH and largely weakening the adsorption of *CO intermediates on the catalyst surface. This study reveals that the unique PdBi bimetallic interface can provide a novel platform to study the reaction mechanism through combining in-situ ATR-SEIRAS and DFT calculations. [ABSTRACT FROM AUTHOR]

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Pear (Pyrus spp.) has the function of clearing heat, reducing fire and moistening the lungs. Not from concentrated (NFC) pear juice can better maintain the nutrition, aroma and taste of pear fruit, which is worth considering as a pear processing product. Fruit raw materials play a key role in the preparation of NFC juice. In order to obtain suitable varieties for NFC pear juice, this study investigated the fruit quality of 16 kinds of pear from China, and the physicochemical characteristics, sensory quality and volatile components of NFC pear juice. The results revealed that there was a great difference among the species. The weight of single fruit varies from 84.03 to 334.96 g and juice yield from 39.39 to 85.22%. For the juice, L* values from 32.74 to 45.13, a* values from − 0.72 to 3.79%, b* values from 2.01 to 11.00. Browning degree from 0.66 to 4.35. Total soluble solids from 8.26 to 12.89%, sugar contents from 1.28 to 6.64%, total acidity from 0.65 to 7.55 g/L, and apparent viscosity from 2.42 to 3.99 mPa s. Total polyphenols from 32.35 to 116.48 mg/100mL, total flavonoid content from 21.14 to 372.32 mg/100mL. The DPPH radical scavenging ability from 60.77 to 96.28%, ABTS radical scavenging ability from 7.5 to 45.60%. 70 volatile components were detected in 16 NFC pear juices, mainly including alcohols, esters and aldehydes, etc. Overall sensory score from Anli (4.45) to Williams pear (7.72). Through correlation analysis and principal component analysis, it was found that the variety of pear fruit was an important factor affecting the quality of fruit juice. [ABSTRACT FROM AUTHOR]

Abstract—In this study, the complete mitochondrial genome (mt genome) of Triosteum pinnatifidum was investigated for the first time. The mt genome was consisted of 803 609 bp, comprised of 62 genes including 19 tRNA genes, 3 rRNA genes and 40 protein-coding genes. We detected protein-coding genes and codon usage, RNA editing sites and repeat sequences. The protein-coding genes substitution rates, DNA segments migration, comparison of six species genomic features were generated. Phylogenetic analysis of 32 species was also taken. A total of 463 RNA editing sites were found in 40 protein-coding genes. Being slightly positive, the GC-skew and AT-skew are 0.0060 and 0.0004, respectively. Most of PCGs have Ka/Ks ratio less than 1, indicating the existence of purifying or negative selection in these genes. This is the first report mt genome in the family Caprifoliaceae and could provide a useful foundation for evolutionary analysis, molecular biology and taxonomy in genus Triosteum and other higher plants. [ABSTRACT FROM AUTHOR]

In this study, flower-like Bi2MoO6/Ag3PO4 composite photocatalysts were synthesized through in-situ chemical precipitation, and their photocatalytic activity for Rhodamine B (RhB) degradation was studied. The structure and activity of the composite catalysts were characterized with XRD, SEM, EDX, TEM, HRTEM, SAED, XPS, UV–Vis diffuse reflection absorption spectrum and photocatalytic degradation experiments. The results showed that the photocatalytic performance of the composite Bi2MoO6/Ag3PO4 was significantly better than that of pure Bi2MoO6 and pure Ag3PO4, and the composite with the composition of 0.1Bi2MoO6/Ag3PO4 showed the best performance in the photocatalytic degradation of Rhodamine B (RhB). The degradation rate of RhB reached up to 98% after visible light exposure for 25 min, and the maximum reaction rate constant measured for 0.1Bi2MoO6/Ag3PO4 was 0.09457 min−1, which was twice that of pure Ag3PO4 and 38 times that of pure Bi2MoO6. After three cycles, the catalytic performance of 0.1Bi2MoO6/Ag3PO4 did not decrease significantly, and 82% of RhB was still degraded. Capture experiments showed that holes (H+) and superoxide anions (O-2·) played a major role in the photocatalytic degradation of RhB using 0.1Bi2MoO6/Ag3PO4, and hydroxyl radicals (OH·) only partially contributed to the activity. The energy level structure of Bi2MoO6/Ag3PO4 was conducive to the separation of photogenerated electrons and holes, and as a result, the service life of photogenerated carriers was prolonged. Notably, the photocatalytic activity of the 0.1Bi2MoO6/Ag3PO4 composite photocatalyst was the highest. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to translate and culturally adapt the immune checkpoint modulator (ICM) subscale of the Functional Assessment of Cancer Therapy-Immune Checkpoint Modulator (FACT-ICM) scale and to validate the FACT-ICM scale in Chinese cancer patients receiving immune checkpoint inhibitors (ICIs) treatment. Methods: In total, 354 cancer patients treated with ICIs were included in our cross-sectional study including 2 phases. Firstly, the ICM subscale was translated and culturally adapted by standardized procedures. Then the FACT-ICM scale was validated, which included item analysis, content validity, floor and ceiling effects, internal consistency reliability, test–retest reliability, construct validity, convergent/divergent validity, and known-group validity. Results: The content validity indexes at the item and scale level of the ICM subscale were greater than 0.8. No floor and ceiling effects were found. The Cronbach's α and McDonald's omega coefficients of the simplified Chinese version of the FACT-ICM scale were 0.935 and 0.936, and the intraclass correlation coefficient was 0.833 (95% confidence interval: 0.574–0.940). Confirmatory factor analysis confirmed the 5-subscale structure of the simplified Chinese version of the FACT-ICM scale (χ2/df = 2.144, RMSEA = 0.057, SRMR = 0.072, and CFI = 0.848). Convergent and divergent validity further supported the construct validity of the simplified Chinese version of the FACT-ICM scale. The known-group validity of the simplified Chinese version of the FACT-ICM scale was confirmed in patients with different physical statuses. Conclusions: The simplified Chinese version of the FACT-ICM scale is a valid and reliable instrument and can be used in clinical practice and research on cancer patients receiving ICIs treatment. [ABSTRACT FROM AUTHOR]

The objective of this study was to systematically investigate how sodium butyrate (SB) affects the gastrointestinal bacteria in newborn calves at different stages before weaning. Forty female newborn Holstein calves (4-day-old, 40 ± 5 kg of body weight) were randomly divided into four groups; each group was supplemented with four SB doses: 0, 15, 30, and 45 g/day (ten replicates) in SB0, SB15, SB30, and SB45 groups, respectively. SB was fed with milk replacer from day 4 to day 60. Rumen fluid and feces were collected on days 2, 14, 28, 42, and 60 for 16S rRNA high-throughput sequencing. Data were analyzed in a complete randomized design and analyzed on the online platform of Majorbio Cloud Platform. The results showed that SB significantly increased the α-diversity in feces, especially Shannon and Chao indices in SB45 and SB30 at day 60 more than in SB15 (P < 0.05). Additionally, SB significantly enhanced Firmicutes growth from day 2 to 28 and also increased Bacteroides abundance from day 28 to 42 in rumen and feces (P < 0.05). SB also significantly inhibited Proteobacteria abundance in rumen and feces during the study period (P < 0.05). SB also promoted some potential beneficial bacterial abundance, including Prevotella, Lachnospiraceae, Clostridium, Ruminococcus, and Muribaculaceae (P < 0.05). Additionally, Escherichia-Shigella abundance at SB0 was significantly lower than in the other groups (P < 0.05). In conclusion, this study firstly reported a dynamic curve showing of the SB effects on bacteria in calves before weaning. This study provides valuable evidence for the development of the gastrointestinal tract of the calves in the early stage of the life. SB supplementation improved the gastrointestinal health by regulating the bacterial populations. Key points: • The gastrointestinal tract of calves has been improved after the SB supplementation. • Microbes were the vital influential factor in the development of calves. • Intervention before weaning is an effective strategy for calf health. [ABSTRACT FROM AUTHOR]

The multiannual delayed gametophyte of kelp species maintains continuous vegetative growth under unsuitable conditions and can restart gametogenesis under suitable conditions. However, the processes and mechanisms of this phenomenon are still poorly understood. To gain insight into the processes and mechanisms of gametogenesis in multiannual delayed gametophytes of the kelp Saccharina japonica, the ultrastructure changes, photosynthetic and biochemical responses, and dynamics of gene expression were investigated. Data were collected at four time points (0, 3, 6, and 9 days) during gametogenesis. After gametogenesis induction there were notable changes in the ultrastructure, including increases in mitochondria and the Golgi bodies, and changes in chloroplast and endoplasmic reticulum structures. The contents of abscisic acid and H2O2 as well as the activities of pivotal respiratory enzymes (malic dehydrogenase and phosphofructokinase) and key antioxidant enzymes (catalase and ascorbate peroxidase) all increased significantly after 3 days of gametogenesis induction, implying that these changes were closely related to the gametophyte's transition from vegetative growth to gametogenesis. Notably, photosynthetic and respiratory indicators both showed significantly upregulated trends after 6 days of induction, indicating that the gametophyte's metabolism was most active during transformation from vegetative growth into gametogenesis. Time-specific DEGs (differentially expressed genes) were identified during the vegetative and reproductive stages of gametophytes. Gene ontology analysis indicated that "cell part", "cellular process" and "binding" represented the largest categories in the DEG datasets. Moreover, the predominant transcription factor families were bHLH, MYB, and C3H in the DEG datasets. There were 8 genes related to peroxisomes, 12 genes related to proteasomes, 4 genes related to oxidative phosphorylation, and 59 genes related to ubiquitin-mediated proteolysis identified as up- or downregulated DEGs at the two key stages during gametogenesis, the initial developmental stage and the oogonia formation stage. [ABSTRACT FROM AUTHOR]

This paper investigates the design issue of the fault-tolerant tracking controller for uncertain nonlinear systems with input delay and actuator faults. Fuzzy logic systems are employed to approximate the uncertainties of the nonlinear systems. A state observer and a disturbance observer are designed to estimate the unmeasurable states and external disturbances, respectively. Moreover, an auxiliary system is applied to make up for the impact of the input delay. Furthermore, with the aid of the backstepping technology and the dynamic surface control method, a disturbance observer-based adaptive fuzzy fault-tolerant tracking controller is designed, which can guarantee that the output signal can track the reference signal greatly, and the other signals are bounded in the closed-loop system in case of input delay and actuator faults. Finally, a practical simulation example is supplied to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Due to its low density, high tensile strength and excellent energy absorption capability, 7B52 laminated (7A52/7A01/7A62 layers) aluminum alloy is a promising material for the application of armored vehicles and tanks. With the rapid development of anti-armor weapons, there is an increasing need for 7B52 laminates with excellent impact resistance. However, the impact failure behaviors and related mechanisms of this laminated alloy remain unclear. In this work, the macro–micro–nonuniform deformation behaviors of a 7B52 laminated aluminum alloy after high-speed impacts (from 2700 to 5000 s−1) were investigated. The results revealed that the plastic deformation was mainly concentrated in the 7A01 and 7A52 layers of the 7B52 laminated aluminum alloy under high-speed impact, indicating nonuniform deformation of this alloy. The ductile 7A01 layer led to the blunting and deflection of cracks formed in the interlaminar 7A62 and 7A01 layers and thus prevented cracks from propagating into the 7A52 layer. Meanwhile, the nonuniform deformation between the 7A52 and 7A62 layers could be justified from adiabatic shear bands and precipitates. Deformation shear bands, transformation shear bands and then both were successively observed in the 7A52 layer, while only slight deformation was present in the 7A62 layer due to a much larger amount of η' precipitates effectively hindering dislocation movement. Therefore, nonuniform deformation was observed in the 7B52 alloy under high-speed impact. [ABSTRACT FROM AUTHOR]

With a long epidemic history and a large number of dengue cases, Guangzhou is a key city for controlling dengue in China. The demographic information regarding dengue cases, and the genomic characteristics of the envelope gene of dengue viruses, as well as the associations between these factors were investigated from 2010 to 2019, to improve the understanding of the epidemiology of dengue in Guangzhou. Demographic data on 44,385 dengue cases reported to the Notifiable Infectious Disease Report System were analyzed using IBM SPSS Statistics v. 20. Dengue virus isolates from patient sera were sequenced, and phylogenetic trees were constructed using PhyML 3.1. There was no statistical difference in the risk of dengue infection between males and females. Unlike other areas in which dengue is endemic, the infection risk in Guangzhou increased with age. Surveillance identified four serotypes responsible for dengue infections in Guangzhou. Serotype 1 remained prevalent for most of the study period, whereas serotypes 3 and 4 were prevalent in 2012 and 2010, respectively. Different serotypes underwent genotype and sublineage shifts. The epidemiological characteristics and phylogeny of dengue in Guangzhou suggested that although it has circulated in Guangzhou for decades, it has not been endemic in Guangzhou. Meanwhile, shifts in genotypes, rather than in serotypes, might have caused dengue epidemics in Guangzhou. [ABSTRACT FROM AUTHOR]

A series of marginal-sea basins and fault-depression basins were formed in eastern China under the background of subduction of the West Pacific plate. Different types of helium-rich natural gas reservoirs (He>1000 ppm, 1 ppm=1 µmol mol−1) have been found in these basins: helium-rich CO2 gas reservoirs, helium-rich N2 gas reservoirs, and helium-rich hydrocarbon gas reservoirs. Based on the analysis of gas geochemical data, the source and accumulation mechanism of helium in these helium-rich natural gas reservoirs were discussed. Helium-rich natural gas has relatively high 3He/4He ratios (0.88–4.91 Ra, average 2.82 Ra). The 3He/4He ratio characteristics of mantle xenoliths and mantle-derived CO2 gas reservoirs indicate that the helium in these helium-rich natural gas reservoirs is mainly mantle-derived (>70%). The original mantle volatile is mainly CO2 with a low helium concentration (He<200 ppm), and the enrichment of mantle-derived helium in the gas reservoir is mainly related to the dissolution and mineralization of CO2. During this process, the CO2/3He ratio decreases from 2×109 to approximately 2×106. As CO2 dissolves and mineralizes, the concentration of conservative gases (He and N2) increases in the remaining CO2 gas proportionally to the loss of CO2. Large amounts of carbonate minerals, such as dawsonite, which are relatively enriched in 13C, are found in CO2 reservoirs in eastern China. The relative enrichment of 12C in residual CO2 gas is important evidence of the dissolution and mineralization of CO2. The relative abundance of mantle-derived helium and N2 gas increases thousands of times during the dissolution and mineralization of CO2, which is the main accumulation mechanism of mantle-derived helium-rich CO2 gas reservoirs and helium-rich N2 gas reservoirs. Helium-rich gas from the mantle is mixed with alkane gas generated by organic matter in the sedimentary basin to form helium-rich hydrocarbon gas reservoirs. [ABSTRACT FROM AUTHOR]

Since the 1920s, fossil erinaceids have been found in several dozen Quaternary localities in China. Previously, most of them were provisionally classified in eurytopic Erinaceus. This limits understanding of the authentic diversity and evolution of Erinaceinae in China and the reconstruction of their paleohabitats. We reviewed all accessible erinaceid fossils found in the Quaternary deposits in China. An erinaceid fragmentary mandible collected from the early Pleistocene deposits in Tianzhen county, Shanxi Province in North China was classified as Mesechinus cf. hughi, which is the oldest definite report of fossil Mesechinus in China. We considered that Erinaceus koloshanensis Young and Liu (1950) from Geleshan, Chongqing Municipality, should be transferred to Mesechinus as M. koloshanensis, and E. olgae Young (1934) from Zhoukoudian, Beijing, should be considered as a synonym of M. dauuricus. Our re-examination supplies a fossil calibration for the previous molecular phylogeny of the Erinaceinae. The earliest Mesechinus appeared in the early Pleistocene with the representative Mesechinus cf. hughi, M. dauuricus occurred in the middle Pleistocene and Erinaceus amurensis is also dated to the middle Pleistocene. Compared with Erinaceus, Mesechinus occupies a narrower niche and could be a potential indicative genus for a woodland or forest environment. [ABSTRACT FROM AUTHOR]

This study aims to examine the association between short-term exposure to ambient PM1, PM1-2.5, and PM2.5 and forced vital capacity (FVC). Population data were obtained from a school-based cross-sectional survey in Shandong in 2014. Distributed lag non-linear models were used to examine the association between exposure to PM1, PM1–2.5, and PM2.5 and FVC at the day of FVC measurement and the previous 6 days (lag 0 to 6 days). A total of 35,334 students aged 9 to 18 years were included in the study, and the mean exposure concentrations of ambient PM1, PM1–2.5, and PM2.5 for them were 47.4 (standard deviation [SD] = 21.3) μg/m3, 32.8 (SD = 32.2) μg/m3, and 80.1 (SD = 47.7) μg/m3, respectively. An inter-quartile range (IQR, 24 μg/m3) increment in exposure to PM1 was significantly associated with a lower FVC at lag 0 and lag 1 day (β = − 80 mL, 95% CI = − 119, − 42, and β = − 37 mL, 95% CI = − 59, − 16, respectively), and an IQR (54 μg/m3) increment in exposure to PM2.5 was significantly associated with a lower FVC at lag 0 and lag 1 day (β = − 57 mL, 95% CI = − 89, − 18, and β = − 34 mL, 95% CI = − 56, − 12, respectively) after adjustment for gender, age, body mass index category, residence, month of the survey, intake of eggs, intake of milk, physical activity, and screen time. No significant associations were observed for PM1–2.5. The inverse associations of PM1 and PM2.5 with FVC were larger in males, younger children, those overweight or obese, and those with insufficient physical activity levels. Short-term exposure to ambient PM1 and PM2.5 was associated with decreased FVC, and PM1 may be the primary fraction of PM2.5 causing the adverse pulmonary effects. Our findings emphasize the need to address ambient PM, especially PM1, pollution for affecting pulmonary health in children and adolescents. [ABSTRACT FROM AUTHOR]

In this article, we study an adaptive finite-time event-triggered command filtered control problem based on output feedback for a class of nonstrict-feedback nonlinear systems with unknown control directions. Firstly, the unknown nonlinear continuous functions in the systems are approached by fuzzy logic systems, and the coordinate transformations and Nussbaum function technique are introduced to settle the problem caused by the unknown control directions in the systems. Then, in order to reduce the communication burden between the controller and the actuator, a finite-time adaptive event-triggered control algorithm is designed by means of backstepping technique. It is proved that the tracking and observer errors are adjusted around zero with a small neighborhood in a finite time and all the signals in the closed-loop systems are bounded. In addition, the command filtering technology based on error compensation system with fractional power is constructed to avoid the complexity explosion issue in the backstepping design process. Finally, the simulation examples are included to verify the availability and superiority of the control approach. [ABSTRACT FROM AUTHOR]

Potassium is the active element of potash fertilizer, its concentration determines the quality of the product. Self-absorption occurs in laser-induced breakdown spectroscopy (LIBS) analysis of potash, since potassium is the major element with a concentration that can reach the level of 95 wt.%. The present work simulated an online analysis of potassium in potash with a laboratory setup, LIBS spectra were recorded on 27 potash samples collected from a factory in Qinghai province in China with different potassium concentrations in the range from 90 to 97 wt.%. The self-absorption correction was applied to the spectra for K I 404.4 nm and K I 693.9 nm lines. Multivariate regression based on machine learning were processed with the self-absorption corrected spectra in order to get a better potassium determination performance compared to that with uncorrected spectra. The results show the effectiveness of self-absorption correction in the improvement of the analytical performance. The obtained multivariate regression model presents a satisfactory performance to fill the requirements of the aimed application of online and real-time analysis of potash on a product transportation belt in a production site with respect to the specific requirements of the related current national standards. [ABSTRACT FROM AUTHOR]

Lightweight Al2NbTixV2Zr (x = 1.0, 1.5, 2.0, 2.5, 3.0) high entropy alloys are fabricated through mechanical milling followed by vacuum hot pressing. The effect of Ti content on microstructure, hardness, mechanical behaviors, and corrosion property of the alloys are investigated. Microstructural studies reveal multiphase structures for this alloy, BCC solid solution matrix and α phase for Ti1.0 and for Ti1.5 alloys while β occurs in Ti2.0, Ti2.5 and Ti3.0 alloys. All sintered bulks exhibit low density in the range of 5.2-5.4 g/cm3. Hardness of Al2NbTixV2Zr alloys fluctuates between 749 to 791 HV to various Ti contents. The varying tendency of hardness is closely related with the content of the secondary phase. The alloys show high yield strength and considerable strain during compression test. Comprehensive property of Al2NbTixV2Zr system is superior to majority of other HEAs. The alloys display good anti-corrosion properties in HNO3, H2SO4, HCl, and NaCl solutions, and the corrosion property of Al2NbTixV2Zr improves with the increasing of Ti content. [ABSTRACT FROM AUTHOR]

Rosa roxburghii pomace was treated by steam explosion (SE) at 0.87 MPa for 97 s. After SE treatment, the Insoluble dietary fiber (IDF) content of Rosa roxburghii pomace decreased from 45.13 ± 0.23 to 30.01 ± 0.15%, and the soluble dietary fiber (SDF) content increased from 9.31 ± 0.07 to 15.82 ± 0.31%. The structure of IDF and SDF after SE showed that the original compact structures were destroyed, and the specific surface areas increased. Thermal analysis showed that the thermal stability of the modified SDF was improved. However, SE did not change the crystal structure and functional group composition of IDF and SDF. Physicochemical analysis indicated that IDF had better hydration capacity after SE treatment, and the oil-holding capacities of IDF and SDF were also significantly improved. SE is an effective method to improve the utilization of Rosa roxburghii pomace and a feasible method for modification of dietary fiber. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) plays an important role in the cycling and toxicity of heavy metals in aquatic systems. However, most studies have focused only on DOM in either water or sediments. This study aimed to analyze the source, composition, and structural characteristics of DOM in both surface water and bottom sediments of the Le'an River and its major tributaries. In addition, the potential ecological risks of three typical heavy metals (Cu, Pb, and Zn) were quantitatively evaluated based on the characteristics of DOM and in situ data. The results showed that sediment DOM is more aromatic and hydrophobic than surface water DOM. Although humic-like components dominated the DOM pool in both surface water and sediments, their sources were different. Surface water DOM is mainly autochthonous, while sediment DOM is controlled by both autochthonous and allochthonous sources. Risk prediction results based on DOM characteristics show that surface water has a higher potential risk of heavy metal release than sediments. Comprehensively considering the ecological risk of water and sediments, high-risk areas were found to be mainly distributed in the upper and middle reaches of the Le'an River. This distribution is attributable to the developed mining and smelting industries in these areas and consistent with the risk assessment results of measured concentrations of heavy metals. This study established a new technique for predicting the ecological risk of aquatic systems based on the characteristics of DOM in surface water and sediments. [ABSTRACT FROM AUTHOR]

In this article, the observer-based adaptive finite-time prescribed performance control issue is studied for a category of nonlinear systems with external disturbances and input delay. The fuzzy logic systems are employed to model the unknown nonlinear terms in the system. The Pade approximation method is utilized to deal with the input delay problem. To estimate the unmeasurable states in the system, a fuzzy state observer is established. By using the finite-time Lyapunov control theory and the backstepping technique, a finite-time adaptive fuzzy controller is designed. The controller can guarantee that the tracking error converges to a prescribed region in a finite time and the boundedness of all signals in the closed-loop system. Finally, a simulation example is included to verify the validity and feasibility of the control method. [ABSTRACT FROM AUTHOR]

In this work, the problem of global adaptive stabilization is solved by output feedback for a family of feedforward nonlinear time-delay systems with uncertain output equation and unknown growth rate. To deal with system uncertainty, a low-gain observer incorporating with novel adaptive gain is first proposed. Next, via output feedback, an adaptive delay-free controller is constructed by combining scaling change with backstepping algorithm. Compared with existing results, the controller proposed is capable of handling both uncertain output equation and unknown delay. With the aid of Lyapunov-Krasovskii functional and Barbălat's lemma, it is shown that the state and its estimate converge asymptotically to zero, and the adaptive gain is bounded. Furthermore, by numerical simulations, the usefulness of the control scheme is illustrated. [ABSTRACT FROM AUTHOR]

In order to investigate the influence of twin on mechanical behavior and microstructural evolution of magnesium alloys under impact loading, high-speed impact tests of magnesium alloys with different twin densities were conducted by Split Hopkinson Pressure Bar under impact pressures of 0.3, 0.5, and 0.7 MPa with deformation temperatures of 150, 200, 250, 300, and 350 °C. The yield strength of magnesium alloy is significantly enhanced by twins under high-speed impact loading. At low-temperature impact deformation, twinning and deformation shear bands are the main accommodation mechanisms for un-twinned magnesium alloy, while with respect to the twinned magnesium alloy, dynamic recrystallization (DRX) could participate in plastic deformation. The appearance of twins could reduce the recrystallized temperature and the critical strain for DRX. The twinned magnesium alloy is benefit for texture weaken during high impact loading. The maximum pole density monotonic decreases with increasing recrystallization fraction and decreasing twin density. [ABSTRACT FROM AUTHOR]

Prevailing lake changes on the Qinghai–Tibetan Plateau (QTP) have occurred. Selin Co, a representative saline lake in the central region of the QTP, has had the largest increase and become the largest endorheic lake in Tibet, but the main cause for its dramatic expansion is still under debate. Based on Landsat images, meteorological data and glacier and permafrost data, the dynamic changes in Selin Co and its surrounding small lakes were systematically discussed, and the driving factors behind these changes were further explored. The results suggest that during 1988–2017, the areas of Bange Co and Cuoe Lake showed slow, overall increasing trends at the rates of 0.28 km2/year and 0.11 km2/year, respectively, and upward trends before 2005 but downward trends afterward. The area of Selin Co substantially increased by 685.8 km2 with a growth rate of 30.39 km2/year, with a slow increase of 27.11 km2 during the period of 1988–1997, a rapid increase of 510.53 km2 during 1997–2005 and an increase of 148.16 km2 during 2005–2017. Accordingly, the lake level and water volume of Bange Co slightly increased by 1.64 m and 0.088 km3, respectively, whereas those of Selin Co significantly rose by 8.138 m and 17.47 km3, respectively. The changes in the areas of Bange Co and Cuoe Lake were mostly related to annual precipitation (AP). The expansion of Selin Co may be partly explained as the discharge from the glacier retreat and permafrost degradation in the watershed. Glacial meltwater has enhanced owing to rising, with a rapid reduction of 165.1 km2 (39%) in the glacier area in the basin between 1980 and 2010. Permafrost degradation has significantly accelerated, with increases in the active layer thickness (ALT) (7.44 cm/year) and soil temperatures at a 15-m depth (0.0346 °C/year). [ABSTRACT FROM AUTHOR]

Purpose: Biochar is used for the stabilization of Pb in soil because of its abundant surface functional groups and excellent pore structure. However, little is known about the long-term performance of biochars. This study aims to evaluate the effect of biochar aging on the adsorption and stabilization of Pb in soil and to provide theoretical guidance for long-term utilization of biochar. Materials and methods: A modified BCR continuous extraction procedure was performed to analyze the effects of three aging methods (natural, freeze–thaw, and high-temperature aging), four biochar species (wheat straw, corn straw, peanut shell, and pine chips chars), and aging time (7, 60, and 150 days) on the chemical fractions of Pb in soil. FTIR, XRD, and BET were used to analyze surface functional groups, composition, and pore structure of biochars, respectively. Results and discussion: The effects of three aging methods on the stabilization of Pb in soil were ordered as high-temperature aging (HT) ≈ freeze–thaw aging (FT) > natural aging (NA). The effects of biochar species were ordered as CSC > WSC ≈ PSC > PCC. The stabilization performance of Pb in soil was enhanced with increasing aging time. The mechanism of Pb stabilization in soil by biochar involves surface complexation, co-precipitation, ion exchange, physical adsorption, and electrostatic attraction. Conclusions: The adsorption and stabilization of Pb in soil were enhanced by biochar aging through decreasing acid extractable Pb and increasing residual Pb. Surface complexation, co-precipitation, and physical adsorption were the main reasons for the enhancement. [ABSTRACT FROM AUTHOR]

Intrahepatic cholangiocarcinoma (CHOL) remains a rare malignancy, ranking as the leading lethal primary liver cancer worldwide. However, the biological functions of integrator complex subunit 8 (INTS8) in CHOL remain unknown. Thus, this research aimed to explore the potential role of INTS8 as a novel diagnostic or therapeutic target in CHOL. Differentially expressed genes (DEGs) in two Gene Expression Omnibus (GEO) datasets were obtained by the "RRA" package in R software. The "maftools" package was used to visualize the CHOL mutation data from The Cancer Genome Atlas (TCGA) database. The expression of INTS8 was detected by performing quantitative reverse transcription-PCR (qRT-PCR) and immunohistochemistry in cell lines and human samples. The association between subtypes of tumour-infiltrating immune cells (TIICs) and INTS8 expression in CHOL was determined by using CIBERSORT tools. We evaluated the correlations between INTS8 expression and mismatch repair (MMR) genes and DNA methyltransferases (DNMTs) in pan-cancer analysis. Finally, the pan-cancer prognostic signature of INTS8 was identified by univariate analysis. We obtained the mutation landscapes of an RRA gene set in CHOL. The expression of INTS8 was upregulated in CHOL cell lines and human CHOL samples. Furthermore, INTS8 expression was closely associated with a distinct landscape of TIICs, MMR genes, and DNMTs in CHOL. In addition, the high INTS8 expression group presented significantly poor outcomes, including overall survival (OS), disease-specific survival (DSS) and disease-free interval (DFI) (p < 0.05) in pan-cancer. INTS8 contributes to the tumorigenesis and progression of CHOL. Our study highlights the significant role of INTS8 in CHOL and pan-cancers, providing a valuable molecular target for cancer research. [ABSTRACT FROM AUTHOR]

The dynamic mechanical behaviors of 7B52 laminated aluminum alloy under different impact deformation conditions were investigated using split Hopkinson pressure bar, optical microscopy, electron backscatter diffraction and transmission electron microscopy. The results show that the 7B52 laminated aluminum alloy displays positive strain rate sensitivity and negative temperature sensitivity. Cracks are formed firstly at the interface between the 7A62 hard layer and the 7A01 middle layer under a low strain rate of 2200 s−1. When the strain rate increases to 3500 s−1, the deformation shear band is firstly formed in the 7A52 soft layer. The deformation shear band transformed to the transition shear band with the increase of strain rate, and then crack initiated. Adiabatic shear bands and cracks are formed in both of the hard and soft layers when samples impacted at a high strain rate (5500 s−1). Most of the cracks and adiabatic shear bands are unable to penetrate the middle layer due to the good toughness of the 7A01 alloy. The deformation of each layer of 7B52 laminated aluminum alloy becomes more uniform when the temperature increases, which was attributed to the reduction of difference in strength among the three layers and the coordinating effect of grain boundary on deformation. [ABSTRACT FROM AUTHOR]

Terahertz (THz) detecting technology has attracted many attentions. In this work, a novel THz detector based on a metal gratings/Si-based blocked-impurity-band (BIB) hybrid structure was designed and theoretically calculated. The highly integrated hybrid structure was found useful for modulating the response wavelength and improving the responsivity of Si-based BIB detector. The enhanced THz absorption of the hybrid device structure of metal gratings and Si-based BIB absorption layer was carefully investigated by finite difference time domain. The peak wavelength can be moved from 26.9 to 36.53 μm when metal gratings (period: 32 μm) were added on the Si-based BIB. The peak absorptivity of the hybrid detector was increased by 87.3 % with the metal gratings, compared with that of conventional Si-based BIB detector. Our results indicate that a highly integrated hybrid device structure can replace the divided band filters, and realize selective resonant enhanced absorption and tunable THz spectral response. [ABSTRACT FROM AUTHOR]

Circular RNA protein kinase, DNA-activated, catalytic subunit (circ_PRKDC) has been found to impede wound healing in diabetic foot ulcers via regulating keratinocyte proliferation and migration. However, the mechanisms underlying circ_PRKDC in skin wound healing remain unclear. The expression of circ_PRKDC, microRNA (miR)-31 and fibrillin 1 (FBN1) was detected using quantitative reverse transcription-polymerase chain reaction and Western blot assays. The migration ability and the changes of matrix metallopeptidase 9 (MMP-9) and MMP2 levels were determined using wound healing, transwell and Western blot assays. The interaction between miR-31 and circ_PRKDC or FBN1 was verified by dual-luciferase reporter assay. The expression of circ_PRKDC was gradually down-regulated in wound edge at 1 and 7 days after injury relative to the unwounded skin. In human epidermal keratinocytes (HEKa), knockdown of circ_PRKDC promoted cell migration partly through up-regulating MMP-2 and MMP9, while circ_PRKDC overexpression showed opposite effects. In a mechanical study, we confirmed that miR-31 was a target of circ_PRKDC, and inhibition of miR-31 reversed the promotive effect of circ_PRKDC knockdown on HEKa migration. Besides that, miR-31 was verified to target FBN1, and ectopic overexpression of miR-31 accelerated HEKa migration via FBN1. Importantly, we also demonstrated that FBN1 overexpression attenuated the effects of circ_PRKDC knockdown on HEKa migration. In all, circ_PRKDC knockdown promoted HEKa migration during wound healing through miR-31/FBN1 axis, suggesting the therapeutic potential for circ_PRKDC on skin wound healing. [ABSTRACT FROM AUTHOR]

Early postoperative injection of botulinum toxin type A (BTxA) can reduce surgical scar hypertrophy. BTxA injection at different time points is associated with different levels of efficacy, but the efficacy of different doses of BTxA for scar management has not investigated. The purpose of this study was to investigate the effect of different doses of BTxA administered early after surgery on scar improvement through a split-scar experiment. The study included 22 patients who underwent surgery between September 2019 and October 2020. High- and low-dose BTxA was randomly administered into each half of the surgical wound closure immediately after surgery. One half of the incision was injected with a low dose (4 U) of BTxA, and the other half was injected with a high dose (8 U). The scars were then evaluated at postoperative 6 months using the modified Stony Brook Scar Evaluation Scale (mSBSES), and patient satisfaction was evaluated using the Visual Analogue Scale (VAS). The occurrence of complications or adverse events was also recorded. Twenty patients completed the study and were analyzed. Compared with the low-dose sides, the high-dose sides had significantly better mSBSES scores and significantly higher VAS scores (p < 0.01, respectively). No serious adverse reactions or post-injection complications were observed. Immediately after the operation, high-dose BTxA (that is within the therapeutic range) injection improved the appearance of postoperative scar more than low-dose injection. [ABSTRACT FROM AUTHOR]

The dynamic compression behavior and microstructure evolution at 400 °C of an extruded Mg–8Gd–4Y–Nd–Zr alloy with different tempers were investigated. The peak-aged samples exhibit the highest compressive strength, followed by as-extruded samples and over-aged samples. The highest dynamic compressive strength of 582 MPa was achieved by peak-aged sample compressed at 1224 s−1. The high strength was attributed to the formation of abundant thermally stable βʹ precipitates and some dynamic precipitates. The dynamic compressive strength of peak-aged sample and over-aged sample is not sensitive to strain rates, while that of the as-extruded sample is sensitive to strain rates. The dynamic compressive strength of the as-extruded alloy can reach 535 MPa when compressed at 2024 s−1. The high strength was mainly ascribed to the formation of numerous dynamic precipitates and the work hardening effect caused by dislocations. The cracks are composed of crack that is 45° to loading direction on the cylindrical surface and crack on the compressed surface. Microstructure observation indicates that the crack was easily propagated along the interface between the adiabatic shear band and matrix, grain boundaries. The equilibrium phase β in over-aged sample was unable to hinder the crack propagation. [ABSTRACT FROM AUTHOR]

Ceramic capacitors require promising energy storage properties to meet the demands of electronic industry which can be tailored by ferroelectric polarization and electrical breakdown strength. Electrical breakdown exhibits close relation to leakage current in advanced dielectric materials when stimulated by high levels of electric field. The suppression of leakage can be an effective strategy to elevate dielectric breakdown. In this work, Zr ions were employed to replace Ti ions in Ba0.3Sr0.7TiO3 ceramics to achieve the improvement of dielectric breakdown and then increase energy storage ability. Zr doping can obviously reduce the leakage current more than an order of magnitude by blocking the path between two adjacent Ti ions and increasing the distance of electron hopping. A promising energy storage density can be obtained with good fatigue endurance upto cycles of 105. This indicates that the strategy of suppressing leakage by trace amount of Zr doping is an effective approach to tailor energy storage behavior of dielectric ceramics. [ABSTRACT FROM AUTHOR]

Background: Due to the evolving nature of the applications of adipose tissue-derived stem cells (ADSCs) and the rapidly growing body of scientific literature, it is difficult to generate a manual compilation and systematic review of ADSCs in plastic and reconstructive surgery. Methods: Bibliographic records were retrieved from the Web of Science Core Collection and analyzed with CiteSpace. Results: We retrieved 691 publications and their references. We identified 52 research categories. Interdisciplinary studies were common. The journals clustered into 13 subnetworks. The top institutions were Stanford University; University of Pittsburgh; University of Tokyo; University of California, Los Angeles; University of California, Davis; New York University; Tulane University; and University of Michigan. National Institutes of Health and National Natural Science Foundation of China provided the most generous financial support. Studies clustered into 22 topics. Emerging trends may include improvement of fat grafting, and application of ADSCs in wound healing, scleroderma, and facial rejuvenation. Conclusion: The present study provides a panoramic view of ADSCs in plastic and reconstructive surgery. Analysis of journals, institutions, and grants could help researchers in different ways. Researchers may consider the emerging trends when deciding the direction of their study. Level of Evidence III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266. [ABSTRACT FROM AUTHOR]

The effect of grain size on adiabatic shear susceptibility of copper was investigated in this paper. Moreover, the results show that the critical time and critical strain corresponding to the stress collapse point decrease with the increase of grain size at the same strain rate, while the widths of adiabatic shear bands (ASBs) increase as grain size increases, indicating that the adiabatic shear susceptibility of copper increases with the increase of grain size. The electron backscatter diffraction (EBSD) experiment shows that the fraction of twin boundaries in large-grain copper is higher than that in small-grain copper before loading. Furthermore, the larger the grain size is, the easier twin will be produced in large-grain copper during deformation, which leads to the twin boundary ratio of large-grain copper will be further higher than that of small-grain copper. The higher fraction of twin boundaries makes large-grain copper have a stronger strain rate hardening effect and thermal softening effect than small-grain copper. Considering that their strain hardening effects are similar, the enhancement of thermal softening caused by the increase of twin boundary ratio exceeds the enhancement of strain hardening effect and strain rate hardening effect, indicating that large-grain copper has a higher adiabatic shear susceptibility. [ABSTRACT FROM AUTHOR]

The effect of the deformation temperature and strain rate on the dynamic mechanical behavior of an extruded Mg-8Gd-4Y-Nd-Zr alloy plate is investigated using optical microscopy, scanning electron microscopy, x-ray diffraction and the split Hopkinson pressure bar methods. The alloy exhibits excellent dynamic compressive strength both at room temperature and high temperatures. The compressive strength of the alloy can reach 569 MPa, 635 MPa and 567 MPa at the deformation conditions of room temperature/2317 s−1, 200°C/1659 s−1, and 300°C/1581 s−1, respectively. The excellent mechanical properties of the alloy at different temperatures are mainly due to the stable rare earth-rich particles and the dynamic precipitates formed at the grain boundaries during compression. Cleavage planes and dimples are the main features of the fracture surface. The number of dimples increases as the deformation temperature increases, while the proportion of cleavage planes decreases with increasing temperature. However, the fracture characteristics are distinct in different regions. A large number of cleavage surfaces can also be observed in certain areas, where the cleavage cracks are easy to propagate, even if the sample is compressed at elevated temperatures. [ABSTRACT FROM AUTHOR]