The influence of sub-temperature quenching temperature on microstructure and properties of 60Si2Mn steel

Influence of sub-temperature quenching temperature on the tensile strength, hardness and toughness of 60Si2Mn steel was studied, and the ferrite content, austenite grain size and martensite morphology of the microstructure of this steel after sub-temperature quenching were analyzed. The results show that duplex microstructure of martensite and ferrite is obtained by sub-temperature quenching of 60Si2Mn steel. The ferrite content decreases with the quenching temperature increasing. The strength and hardness of 60Si2Mn steel increase, however, its toughness decreases in the range of 770~810℃. The maximum strength and hardness can be obtained by quenching at 800℃, but the strength and hardness decease above 800℃. The small amount of strip ferrite is distributed among martensite lamellar to improve the toughness of the steel. All martensite structure can be obtained by quenching at 810℃

Genetic diversity of Shaanxi soybean landraces based on agronomic traits and SSR markers

Publisher's version/PDFGenetic diversity of a primary core collection of 91 soybean landraces from Shaanxi Province, China, was analyzed using simple sequence repeat (SSR) markers and agronomic traits. A total of 250 alleles were detected in the 91 soybean accessions, with a mean of 7.14 alleles per locus. The mean of polymorphism information content (PIC) was 0.26, ranged from 0.11 for Satt184 to 0.60 for Satt242. UPGMA cluster analysis and PCA analysis clearly showed that, 91 accessions formed two major clusters which generally correspond to geographic origin. Cluster I contained 76 soybean landraces and it was further separated into five subgroups (I-1 to I-5). Cluster II (northern group) included 15 accessions from northern Shaanxi. Group I-1 (Guanzhong group) contained 19 landraces, with 16 from Guanzhong, 3 from northern Shaanxi. Group I-2 (southern group I) composed of 13 accessions from southern Shaanxi and 2 from Guanzhong. Group I-3 (mixture group) contained 18 landraces, with 10 landraces from Guanzhong and 8 from southern Shaanxi. Group I-4 (southern group II) contained 21 accessions, of which 20 from southern Shaanxi and 1 from northern Shaanxi. Group I-5 (southern group III) included only 2 southern Shaanxi landraces. AMOVA analysis showed that, a significant proportion of variance (94.28%) was due to variation within populations

<i>Picea wilsonii</i> Transcription Factor PwNAC38 Promotes Drought and Salt Tolerance in Transgenic <i>Arabidopsis</i> and Apple Calli

The mechanism of Picea wilsonii adapting to abiotic stress remains largely unknown. NAC (NAM, ATAF and CUC) transcription factors play significant roles in plant response to adverse environments. In this study, based on our previous RNA-seq, we analyzed the expression patterns of PwNAC38, and revealed its functions in the process of PwNAC38-mediated stress responses. An open-reading frame, encoding PwNAC38 protein with 330 amino acids, was isolated from the cDNA library, a process which can be induced by drought, salt and ABA treatment. Subcellular localization and yeast experiments showed that PwNAC38 was a nuclear-localized transcription factor, and could form homodimers. The full length of PwNAC38 showed transcriptional activity, while the truncated segments, C-PwNAC38 (156–330 aa) and N-PwNAC38 (1–156 aa), did not. The constitutive expression of PwNAC38 (OE lines) in Arabidopsis did not exert influence on the growth of transgenic plants under normal conditions, whereas transgenic seedlings showed higher survival rates, and the seeds had stronger vigor and a higher germination rate under drought and salt stress. The seed germination and root growth of PwNAC38 OE lines were significantly inhibited in the presence of ABA, suggesting the hypersensitivity of PwNAC38 to ABA treatment. Physiological assays showed that the activity of antioxidant enzymes, such as SOD and POD, increased, and that the accumulation of superoxide anion decreased, in OE lines under stress conditions. Moreover, overexpression of PwNAC38 significantly improved drought and salt tolerance in apple calli. A qRT-PCR assay showed that overexpression of PwNAC38 in Arabidopsis promoted the expression of drought or ABA-responsive genes ATHB-7, ANAC019, ERD1, DREB2A, RD29A, ABI5 and NCED3. Taken together, our results revealed that PwNAC38 is positively involved in plants’ response to drought and salt stress by enhancing ROS scavenging efficiency, and is partially dependent on the ABA signaling pathway

Anti-GPIb/IX autoantibodies are associated with poor response to dexamethasone combined with rituximab therapy in primary immune thrombocytopenia patients

This retrospective study aimed to evaluate whether anti-glycoproteins (GPs) autoantibodies can be used as predictors of response to high-dose dexamethasone combined with rituximab (DXM-RTX) in the treatment of primary immune thrombocytopenia (ITP) patients. One-hundred twenty-six ITP patients were included and retrospectively analyzed, 66.7% of anti-GPIb/IX and 65.9% of anti-GPIIb/IIIa autoantibodies. Results showed that overall response (OR) and complete response (CR) rates of patients without anti-GPIb/IX autoantibodies to DXM-RTX were significantly higher than those with anti-GPIb/IX autoantibodies at 4 weeks (OR: 73.8% vs. 47.6%, CR: 50.0% vs. 26.2%; P < 0.05) and 6 months (OR: 71.4% vs. 45.2%, CR: 42.9% vs. 25.0%; P < .05). Furthermore, patients with anti-GPIb/IX single-positivity exhibited higher resistance to DXM-RTX than patients with anti-GPIIb/IIIa single-positivity at 4 weeks (OR: 37.5% vs. 78.3%; P < .05) and 6 months (OR: 29.2% vs. 78.3%; P < .05). Multivariable logistic regression analysis revealed that anti-GPIb/IX autoantibodies and megakaryocytes were associated with the OR rate of patients at both 4 weeks and 6 months, and anti-GPIb/IX autoantibodies at 4 weeks represented the only significant factor affecting OR rate with DXM-RTX (F = 9.128, P  = .003). Therefore, platelet anti-GPIb/IX autoantibodies might predict poor response to DXM-RTX in ITP patients

Green manure incorporation enhanced soil labile phosphorus and fruit tree growth

IntroductionThe incorporation of green manures substantially enhances the conversion of external phosphorus (P) fertilizers and soil-reserved P into forms readily available to plants. The study aims to evaluate the influence of green manure additions on soil phosphorus dynamics and citrus growth, considering different green manure species and initial soil phosphorus levels. Additionally, the research seeks to elucidate the microbiological mechanisms underlying the observed effects.MethodsA citrus pot experiment was conducted under both P-surplus (1.50 g·P·kg-1) and P-deficient (0.17 g·P·kg-1) soils with incorporating legume (Leg), non-legume (Non-Leg) or no green manure residues (CK), and 18O-P labeled KH2PO4 (0.5 g, containing 80‰ δ18Op) was additionally introduced to trace the turnover characteristics of chemical P fertilizer mediated by soil microorganisms.Results and discussionIn P-surplus soil, compared with the CK treatment, the Leg treatment significantly increased soil H2O-Pi (13.6%), NaHCO3-Po (8.9%), NaOH-Pi (9.5%) and NaOH-Po (30.0%) content. It also promoted rapid turnover of P sources into H2O-Pi and NaHCO3-Pi pools by enhancing the phoC (576.6%) gene abundance. In contrast, the Non-Leg treatment significantly augmented soil H2O-Pi (9.2%) and NaHCO3-Po (8.5%) content, facilitating the turnover of P sources into NaHCO3-Pi pools. Under P-deficient soil conditions, compared with the CK treatment, the Leg treatment notably raised soil H2O-Pi (150.0%), NaHCO3-Pi (66.3%), NaHCO3-Po (34.8%) and NaOH-Pi (59.0%) content, contributing to the transfer of P sources into NaHCO3-Pi and NaOH-Pi pools. This effect was achieved through elevated ALP (33.8%) and ACP (12.9%) activities and increased pqqC (48.1%), phoC (42.9%), phoD (21.7%), and bpp (27.4%) gene abundances. The Non-Leg treatment, on the other hand, led to significant increases in soil NaHCO3-Pi (299.0%) and NaHCO3-Po (132.6%) content, thereby facilitating the turnover of P sources into NaHCO3-Pi and NaOH-Pi pools, except for the phoC gene abundance. Both Leg and Non-Leg treatments significantly improved citrus growth (7.3-20.0%) and P uptake (15.4-42.1%) in P-deficient soil but yielded no substantial effects in P-surplus soil. In summary, introducing green manure crops, particularly legume green manure, emerges as a valuable approach to enhance soil P availability and foster fruit tree growth in orchard production

Soil Texture and Its Relationship with Environmental Factors on the Qinghai–Tibet Plateau

Soil texture data are the basic input parameters for many Earth System Models. As the largest middle–low altitude permafrost regions on the planet, the land surface processes on the Qinghai–Tibet Plateau can affect regional and even global water and energy cycles. However, the spatial distribution of soil texture data on the plateau is largely unavailable due to the difficulty of obtaining field data. Based on collection data from field surveys and environmental factors, we predicted the spatial distribution of clay, silt, and sand contents at a 1 km resolution, from 0–5, 5–15, 15–30, 30–60, 60–100, and 100–200 cm soil depth layers. The random forest models were constructed to predict the soil texture according to the relationships between environmental factors and soil texture data. The results showed that the soil particles of the QTP are dominated by sand, which accounts for more than 70% of the total particles. As for the spatial distribution, silt and clay contents are high in the southeast plateau, and low values of silt and clay mainly appeared in the northwest plateau. Climate and NDVI values are the most important factors that affect the spatial distribution of soil texture on the QTP. The results of this study provide the soil texture data at different depths for the whole plateau at a spatial resolution of 1 km, and the dataset can be used as an input parameter for many Earth System Models

Soil Texture and Its Relationship with Environmental Factors on the Qinghai&ndash;Tibet Plateau

Soil texture data are the basic input parameters for many Earth System Models. As the largest middle&ndash;low altitude permafrost regions on the planet, the land surface processes on the Qinghai&ndash;Tibet Plateau can affect regional and even global water and energy cycles. However, the spatial distribution of soil texture data on the plateau is largely unavailable due to the difficulty of obtaining field data. Based on collection data from field surveys and environmental factors, we predicted the spatial distribution of clay, silt, and sand contents at a 1 km resolution, from 0&ndash;5, 5&ndash;15, 15&ndash;30, 30&ndash;60, 60&ndash;100, and 100&ndash;200 cm soil depth layers. The random forest models were constructed to predict the soil texture according to the relationships between environmental factors and soil texture data. The results showed that the soil particles of the QTP are dominated by sand, which accounts for more than 70% of the total particles. As for the spatial distribution, silt and clay contents are high in the southeast plateau, and low values of silt and clay mainly appeared in the northwest plateau. Climate and NDVI values are the most important factors that affect the spatial distribution of soil texture on the QTP. The results of this study provide the soil texture data at different depths for the whole plateau at a spatial resolution of 1 km, and the dataset can be used as an input parameter for many Earth System Models

Development of SNP, KASP, and SSR Markers by BSR-Seq Technology for Saturation of Genetic Linkage Map and Efficient Detection of Wheat Powdery Mildew Resistance Gene <i>Pm61</i>

The gene Pm61 that confers powdery mildew resistance has been previously identified on chromosome arm 4AL in Chinese wheat landrace Xuxusanyuehuang (XXSYH). To facilitate the use of Pm61 in breeding practices, the bulked segregant analysis-RNA-Seq (BSR-Seq) analysis, in combination with the information on the Chinese Spring reference genome sequence, was performed in the F2:3 mapping population of XXSYH &#215; Zhongzuo 9504. Two single nucleotide polymorphism (SNP), two Kompetitive Allele Specific PCR (KASP), and six simple sequence repeat (SSR) markers, together with previously identified polymorphic markers, saturated the genetic linkage map for Pm61, especially in the proximal side of the target gene that was short of gene-linked markers. In the newly established genetic linkage map, Pm61 was located in a 0.71 cM genetic interval and can be detected in a high throughput scale by the KASP markers Xicsk8 and Xicsk13 or by the standard PCR-based markers Xicscx497 and Xicsx538. The newly saturated genetic linkage map will be useful in molecular marker assisted-selection of Pm61 in breeding for disease resistant cultivar and in its map-based cloning