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The influence of chromium‐bearing filler sand on the transformation of inclusions in high‐Mn and high‐Al steel under various reaction times and Mn content levels is studied, and the mechanism of filler sand intrusion into the steel matrix is analyzed. It is demonstrated that an inclusion containing Cr2O3 is discovered. The evolution pathway of oxide inclusions is identified as Al2O3–MnO → Al2O3–MnO–SiO2 → Al2O3–MnO–SiO2–Cr2O3(Cr2O3 + MnO–SiO2) → Al2O3–MnO–Cr2O3–MgO·Al2O3. It is noteworthy that Cr2O3 inclusions tend to diffuse from the outside inward, but the internal content remains almost unchanged, which is due to the strong diffusion hindrance of SiO2. The formation of a liquid phase in the filler sand is a necessary condition for its infiltration into the steel matrix. The critical liquid‐phase content that results in the formation of Cr2O3 inclusions is 42%, which contains 5–8% of Cr2O3. The formation of pore channels provides favorable conditions for sand penetration, with the maximum penetration depth reaching up to 29 mm. Large sand inclusion particles reach millimeter scale in size and are distributed quite randomly. Chemical reactions at the steel/sand interface can lead to an increase in the total oxygen (T.O) content in the steel. The reaction time has little effect on the T.O content, while the Mn content in the steel has a significant impact, with an increase of up to 41 ppm. During the smelting stage, the filler sand can enter the molten steel, thereby affecting the quality of the product. [ABSTRACT FROM AUTHOR]

Developing novel filler sands has garnered significant interest in improving the ladle's free‐opening rate and enhancing the cleanliness of high‐Mn and high‐Al steel. Laboratory studies explore the effect of adding Cr2O3 powder on the sintering behavior of chromite‐based filler sands. Furthermore, interfacial phenomena are examined between the sands and the steel grades, varying in Mn contents. The results demonstrate that adding Cr2O3 power plays a role in inhibiting the liquid phase formation in the sand. With a 16% addition, the steel (Mn mass% = 30) reacts with the sand, leading to the shape of a spinel phase, specifically (Mn, Fe, Mg)O·(Al, Cr)2O3, which facilitates the separation of the liquid phase. The reduction of FeO to Fe by Mn, Al, and C in steel, especially Al, is hindered by adding Cr2O3, resulting in a suitable sintering degree that ultimately benefits ladle free‐opening. SiO2 is crucial for forming the liquid phase during the sintering process. The SiO2 content of the sand should be about 20% to achieve optimal sintering effects. Chromite sand for casting is not suitable for the steels. The mixed sand presented in the current study demonstrates potential as a suitable filler sand for the steel (20 ≤ Mn mass% ≤ 30). [ABSTRACT FROM AUTHOR]

BACKGROUND: Velvetleaf (Abutilon theophrasti Medik.), primarily a cropland weed, exerts adverse impacts on the productivity of various crops, including soybean (Glycine max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.), by hindering their vegetative growth. However, the interference mechanism of velvetleaf on the three crops remains unclear. RESULTS: The inhibitory effect of velvetleaf water extract on the germination and growth of soybean, wheat, and maize was determined in pot experiments and field trials. Four phenolic acids were identified as allelochemicals: protocatechuic acid (PA), gallic acid (GA), chlorogenic acid (CHA), and vanillic acid (VA). These allelochemicals were detected in different parts (leaves, roots, and stems) of velvetleaf, and in the rhizosphere soil of tested crops over the range of 1.19–556.23 μm kg−1. These allelochemicals were administered in approximate concentrations as in velvetleaf roots and rhizosphere soil, and their effects varied with crop species and velvetleaf parts. The allelochemicals generally had low‐dose stimulation and high‐dose inhibition effects on the growth of soybean, wheat, and maize. Furthermore, the biomass distribution of these crops was affected by allelochemicals in the soil. In field trials, the allelochemicals significantly (P < 0.05) inhibited the growth of all tested crops over the whole growth period, and PA showed a significant (P < 0.05) inhibitory effect on the yield of soybean, wheat, and maize. CONCLUSION: GA, PA, CHA, and VA in velvetleaf aqueous extracts were identified as allelochemicals that play an inhibitory role on three crops. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Previous studies reported that miR-146a was involved in small intestine ischemia-reperfusion (I/R) injury, but the mechanism is largely vague. Here, we aimed to identify the change of miR-146a in patients with mesenteric ischemia and explore the potential regulatory mechanism of miR-146a in intestine epithelial cells survival under ischemia and I/R injury. The plasma of 20 patients with mesenteric ischemia and 25 controls was collected to examine the miR-146a expression by qPCR. Rat intestinal epithelial cells (IEC-6) and 24 male Sprague-Dawley rats were included to build ischemia and I/R model in vitro and in vivo. The qPCR results showed that miR-146a decreased both in the plasma of patients with mesenteric ischemia and in IEC-6 cells and rat small intestine tissues in ischemia and I/R model compared to controls. Both the in vitro and in vivo results showed that I/R resulted in more severe apoptotic injury than ischemia. Cleaved-caspase 3, TLR4, TRAF6, and nuclear NF-κB p65 were up-regulated accompanying reduced XIAP and SOCS3 expression in intestinal ischemia and I/R injury. After up-regulation of miR-146a in IEC-6 cells, increased cell survival and decreased cell apoptosis were observed, concomitant with decreased cleaved-caspase 3 and down-regulated TLR4/TRAF6/NF-κB pathway. What is more, this protective effect was blocked by TRAF6 overexpression and increased nuclear NF-κB p65 nuclear. Taken together, this study revealed that miR-146a expression was decreased in small intestine ischemia and I/R injury. And miR-146a improves intestine epithelial cells survival under ischemia and I/R injury through inhibition TLR4, TRAF6, and p-IκBα, subsequently leading to decreased NF-κB p65 nuclear translocation. [ABSTRACT FROM AUTHOR]

Background and aims Human mutL homologl ( MLH1) works coordinately in sequential steps to initiate repair of DNA mismatches, and aberrant MLH1 expression is related to spermatogenetic malfunction. In the present study, MLH1 expression in patients with azoospermia was investigated, and moderating effects of miR-188-3p on MLH1 expression and spermatogenesis were identified. Methods Testicular tissues from 16 patients with obstructive azoospermia ( OA) and non-obstructive azoospermia ( NOA), and tissues of eight healthy patients were collected. Real-time PCR, Western blotting and immunohistochemical staining were used to detect MLH1 expression. Chromatin immunoprecipitation assay and luciferase reporter assay were performed to evaluate histone acetylation level of miR-188-3p and relationships between miR-188-3p and MLH1. Results Testicular MLH1 expression at mRNA and protein levels was significantly increased, while miR-188-3p expression was lower in patients with OA and NOA than that in controls. Reduced histone acetylation level of miR-188-3p promoter was observed in patients with azoospermia. Overexpression/inhibition of HDAC1, but not HDAC2, contributed to the significant reduction/increase of miR-188-3p expression. miR-188-3p targeted 3′ UTR of MLH1 and regulated MLH1 expression. miR-188-3p inhibitor led to elevation of apoptotic level of spermatogenic cells in mice, while this effect was reversed by si- MLH1. Conclusion Down-regulation of miR-188-3p by reducing histone acetylation up-regulated MLH1 expression and contributed to promotion of apoptosis in spermatogenic cells, in patients with azoospermia. [ABSTRACT FROM AUTHOR]

Suicide attempts constitute a serious clinical problem. People who have attempted suicide are at an elevated risk for additional suicide attempts, but there is limited evidence regarding the predictors of suicidality of suicide attempters following case management services. In the present study the indicators of suicidality after case management were examined. A total of 1,056 subjects who had recently attempted suicide were recruited from January 1, 2011, to June 30, 2011. The suicide prevention center of Kaohsiung City in Taiwan provided case management services and followed up on suicide attempt cases for 6 months. The salient factors for repeat suicide attempts were estimated using a logistic regression analysis. The results showed that multiple factors, including a 'willingness to receive mental health services during a crisis,' 'social support,' 'a history of mental disorders,' and 'a history of suicide,' could predict repeat suicide attempts with hazard ratios (0.58, 0.54, 3.84, 1.51) and 95% confidence interval (0.39-0.86, 0.36-0.83, 2.41-6.10, 1.03-2.21). The four factors mentioned above were the most accurate predictors of subsequent suicidality when case management services were utilized after 6 months of follow-up. The findings of our study could help clarify future strategies for suicide prevention. [ABSTRACT FROM AUTHOR]

Better pregnancy outcomes can be obtained by human mature oocyte vitrification, but many problems remain to be resolved in human mature oocyte vitrification. Since mature oocyte development possesses its own maturity cycle, there should be the optimal timing for mature oocyte vitrification. The purpose of this study was to observe the effects of frozen timing on the spindle density, the angle between the polar body and spindle, and embryo development of intracytoplasmic sperm injection (ICSI) in vitrified mouse mature oocytes and explore its possible mechanism. Mouse oocytes were randomly divided into three groups according to different frozen timing including Groups A, B, and C in which oocytes were vitrified within 2 h after ovum pick-up, and 3-4 and 5-6 h after ovum pick-up, respectively. Spindle-related parameters were measured, ICSI was performed. The spindle occurrence rate of vitrified-thawed oocytes was 98.4% in Group A, 82.3% in Group B, and 75.8% in Group C, without statistical differences between pre-vitrification and post-thawing and among the three groups ( P > 0.05). The angles between the polar body and spindle were larger after thawing than before vitrification ( P < 0.01). The spindle retardance values were lower after thawing than before vitrification in Groups B and C ( P < 0.05), but higher in Group A ( P < 0.05). The spindle retardance values before vitrification were higher in Group B than in Groups A and C ( P < 0.05), but the spindle retardance value, oocyte survival and two-cell rate after thawing were higher in Group A than in Groups B and C ( P < 0.05). There were no statistical differences in ICSI fertility rate between the three groups ( P > 0.05). The damage on the spindle is the slightest and embryo quality is the highest in the mouse oocytes vitrified within 2 h after ovum pick-up. The spindle retardance value is more valuable than the spindle occurrence rate in the evaluation of vitrified-thawed oocyte quality, and is positively correlated with embryo quality. [ABSTRACT FROM AUTHOR]

Summary 1. The aim of the present study was to determine whether ligustrazine (2,3,5,6-tetramethylpyrazine; TMP) exerts a cardioprotective effect during myocardial ischaemia reperfusion (IR), and to investigate the underlying mechanisms and the role of endothelial nitric oxide synthase (eNOS) in cardioprotection. 2. Sprague-Dawley rats were divided into a sham group and five IR groups: IR control, TMP pretreated, TMP + wortmannin (a phosphatidylinositol 3-kinase (PI3K) inhibitor), NG-nitro-L-arginine methyl ester (L-NAME; a NOS inhibitor) and TMP + L-NAME. IR was produced by 35 min of regional ischaemia followed by 120 min of reperfusion. Myocardial infarct size, oxidative stress, myocardial apoptosis, nitric oxide (NO) production, and expression of phosphorylated protein kinase B (Akt) and eNOS were measured. 3. TMP markedly decreased infarct size and attenuated myocardial apoptosis, as evidenced by a decrease in the apoptotic index and reduced caspase-3 activity. TMP treatment caused a marked increase in NO production. Cotreatment with wortmannin or L-NAME completely blocked the TMP-induced NO increase. TMP induced phosphorylation of Akt at Ser 473 (1.61 ± 0.18 vs 0.79 ± 0.10 in the IR control group) and phosphorylation of eNOS at Ser1177 (1.87 ± 0.33 vs 0.94 ± 0.22 in the IR control group). Wortmannin abrogated the phosphorylation of Akt and eNOS induced by TMP. 4. These data suggest that ligustrazine has anti-apoptotic and cardioprotective effects against myocardial IR injury and that it acts through the PI3K/Akt pathway. In addition, the phosphorylation of eNOS with subsequent NO production was found to be an important downstream effector that contributes significantly to the cardioprotective effect of TMP. [ABSTRACT FROM AUTHOR]