Effect of Different Cooling Rates in High Rheological Rate Forming Process on Mechanical Properties of Zr57Cu20Al10Ni8Ag5 Bulk Metallic Glass

Xiao‑Bo Mei,Bao‑Chuan Liu,Wei Jiang,Quan Xu,Qi‑Dong Zhang,Yu‑Bai Ma,Fang‑Qiu Zu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.9

The influence of cooling rates on the mechanical properties of a Zr-based bulk metallic glass prepared with high rheologicalrate forming (HRRF) was investigated and compared with traditional suction cast methods. Amorphous samples of Zr57Cu-20Ni8Al10Ag5 were prepared in copper molds with different sizes in order to obtain different cooling rates for both HRRFand traditional cast methods. These specimens were subjected to compression experiments, including microhardness testing,X-ray diffraction testing and differential scanning calorimetry analysis. The results indicate that the plasticity of the samplesformed by HRRF are higher than that of the as-cast ones at the same cooling rates, while the microhardness manifests theopposite principle. As the cooling rate increases further, the difference in plasticity further increases between two methods,indicating that the plasticity of metallic glasses is more sensitive to cooling rates during the HRRF process. At the core ofthis phenomenon is the fact that HRRF methods can introduce more free volume into glasses than traditional cast methodswith an elevated cooling rate are able to.

Transcriptome profiling of rubber tree (Hevea brasiliensis) discovers candidate regulators of the cold stress respo

Xiao‑Xiao Gong,Bing‑Yu Yan,Jin Hu,Cui‑Ping Yang,Yi‑Jian Li,Jin‑Ping Liu,Wen‑Bin Liao 한국유전학회 2018 Genes & Genomics Vol.40 No.11

Tropical plant rubber tree (Hevea brasiliensis) is the sole source of commercial natural rubber and low-temperature stress is the most important limiting factor for its cultivation. To characterize the gene expression profiles of H. brasiliensis under the cold stress and discover the key cold stress-induced genes. Three cDNA libraries, CT (control), LT2 (cold treatment at 4 °C for 2 h) and LT24 (cold treatment at 4 °C for 24 h) were constructed for RNA sequencing (RNA-Seq) and gene expression profiling. Quantitative real time PCR (qRT-PCR) was conducted to validate the RNA-Seq and gene differentially expression results. A total of 1457 and 2328 differentially expressed genes (DEGs) in LT2 and LT24 compared with CT were respectively detected. Most significantly enriched KEGG pathways included flavonoid biosynthesis, phenylpropanoid biosynthesis, plant hormone signal transduction, cutin, suberine and wax biosynthesis, Pentose and glucuronate interconversions, phenylalanine metabolism and starch and sucrose metabolism. A total of 239 transcription factors (TFs) were differentially expressed following 2 h or/and 24 h of cold treatment. Cold-response transcription factor families included ARR-B, B3, BES1, bHLH, C2H, CO-like, Dof, ERF, FAR1, G2-like, GRAS, GRF, HD-ZIP, HSF, LBD, MIKC-MADS, M-type MADS, MYB, MYB-related, NAC, RAV, SRS, TALE, TCP, Trihelix, WOX, WRKY, YABBY and ZF-HD. The genome-wide transcriptional response of rubber tree to the cold treatments were determined and a large number of DEGs were characterized including 239 transcription factors, providing important clues for further elucidation of the mechanisms of cold stress responses in rubber tree.

Effect of Prior Microstructures on Cementite Dissolution Behavior During Subcritical Annealing of High Carbon Steels

Xiao‑Yu Zhao,Xian‑Ming Zhao,Chun‑Yu Dong,Yang Yang,Huai‑Bin Han 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.6

The variation of the morphology and distribution of cementite particles in different prior structures with spheroidizingannealing process has been proceeded in this paper. It is found that the dissolution and coarsening progresses of variousinitial structures in spheroidizing annealing process are quite asynchronous due to the different interlamellar spacing. Thedissolution rate of degenerated pearlite (D-P) with finer interlamellar spacing is faster. The granular cementite in the spheroidizedmicrostructure is fine, uniform and dense. The mean diameter of spherical cementite is refined to 233 nm. However,the initial structure of degenerated pearlite (D-P) is highly sensitive to the austenitization temperature. The cementite iseasy to be coarsened under high austenitizing temperature. The coarsening is accompanied by the gradual increase of theCr content in the cementite, which increases the stability of the cementite. Therefore, the optimal austenitizing temperaturefor degenerated pearlite (D-P) is suggested to be 770 °C.

Metabolomic analysis of biochemical changes in the tissue and urine of proteoglycan-induced spondylitis in mice after treatment with moxibustion

Xiao Xu,Ya-Nan Shi,Rong-Yun Wang,Cai-Yan Ding,Xiao Zhou,Yu-Fei Zhang,Zhi-Ling Sun,Zhi-Qin Sun,Qiu-Hua Sun 한국한의학연구원 2021 Integrative Medicine Research Vol.10 No.1

Background: Moxibustion is widely used in East Asian countries to manage the symptom of rheumatic diseases. The aim of this study was to identify potential metabolic profiles of moxibustion on relieving ankylosing spondylitis (AS) mice through UHPLC-Q-TOF/MS metabolomic study. Methods: Thirty-two female Balb/c mice were randomized into healthy control (HC), AS model, moxibustion at acupuncture points (MA) in AS model, and moxibustion at non-acupuncture points (MNA) AS model groups. Moxibustion was administered daily at GV4, bilateral BL23 and bilateral ST36 acupuncture points for four weeks in the MA group. The overall health status, the thickness of hind paws and the tissue concentrations of IL-1β, PGE2, IL-6 and TNF-α were assessed. The UHPLC-Q-TOF/MS was used to explore the perturbations of endogenous metabolites in tissue and urine of AS model mice intervened by moxibustion. Results: Compared with the AS group, the overall health status was significantly improved after 4-week moxibustion intervention (p < 0.05). The results also showed that MA significantly reduced the levels of paw thickness and decreased the levels of four cytokines in the tissue (p < 0.01). Thirty-seven endogenous metabolites identified by the OPLS-DA were considered to be contributing to therapeutic effects of moxibustion. Moreover, metabolic pathway analysis further revealed that the identified metabolites were mainly involved in TCA cycle, Lipid metabolism, Amino Acid metabolism, Intestinal flora metabolism and Purine metabolism. Conclusions: UHPLC-Q-TOF/MS based metabolomics approach, as a novel and powerful tool, can help us to gain the insights into potential mechanisms of action of moxibustion for AS.

Production of Cellulase by Trichoderma reesei Rut C30 in Wheat Bran - containing Media

( Xiao Bin Yu,Hyun Shik Yun,Yoon Mo Koo ) 한국미생물생명공학회 1998 Journal of microbiology and biotechnology Vol.8 No.3

Risk Factors of Postoperative Cerebrospinal Fluid Leak After Craniovertebral Junction Anomalies Surgery: A Case-Control Study

Yu Xiao,Bing Wang,Yulian Chen,Lingqiang Chen,Zhenkai Lou,Zhiqiang Gong 대한척추신경외과학회 2023 Neurospine Vol.20 No.1

Objective: To identify potential risk factors for cerebrospinal fluid (CSF) leakage after craniovertebral junction (CVJ) anomaly surgery and to provide a reference for clinical practice. Methods: Sixty-six patients who underwent elective CVJ anomaly surgery during a 6-year period (April 2013 to September 2019) were retrospectively included. Research data were collected from the patients’ medical records and imaging systems. Patients were divided into CSF leak and no CSF leak groups. Univariate tests were performed to identify potential risk factors. For statistically significant variables in the univariate tests, a logistic regression test was used to identify independent risk factors for CSF leakage. Results: The overall prevalence of CSF leakage was 13.64%. Univariate tests showed that a basion-dental interval (BDI) > 10 mm and occipitalized atlas had significant intergroup differences (p < 0.05). Multivariate analysis indicated that a BDI > 10 mm was an independent risk factor for CSF leakage, and patients with CVJ anomalies with a BDI > 10 mm were more likely to have postoperative CSF leaks (odds ratio, 14.67; 95% confidence interval, 1.48–30.88; p = 0.004). Conclusion: It is necessary to maintain vigilance during CVJ anomaly surgery in patients with a preoperative BDI > 10 mm to avoid postoperative CSF leaks.

Axial Resistance of Bored Piles Socketed into Soft Rock

Xiao-yu Chen,Ming-yi Zhang,Xiao-yu Bai 대한토목학회 2019 KSCE Journal of Civil Engineering Vol.23 No.1

Three fully-instrumented full-scale static load tests were conducted on three 0.8-m-diameter bored piles socketed at 3.2 m deep into argillaceous siltstone (1.6 and 1.6 deep into strong and medium decomposed siltstones, respectively) in Qingdao, China. About 50% of head load was transmitted and supported by base resistance at the end of the tests. Totally 53 test piles socketed into soft rock with unconfined compressive strength less than 20 MPa in Qingdao were reviewed. The measured side resistance along shaft socked into rock was compared with prediction using empirical methods in literatures based on database from Qingdao projects.

Transcriptional activation of insulin-like growth factor binding protein 6 by 17β-estradiol in SaOS-2 cells

Yu-yan Zhao,Lei Guo,Xiao-juan Zhao,Hong Liu,Tian Lei,Dong-jie Ma,Xiao-yu Gao 생화학분자생물학회 2009 Experimental and molecular medicine Vol.41 No.7

Osteoblasts can synthesize the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs), which may either enhance or attenuate IGF-stimulated bone cell proliferation. Since estrogen induced osteoblastic differentiation and proliferation through an estrogen- responsive gene in target cells, we investigated the effects of estrogen on IGFBP-6 expression in the human osteoblastic-like cell line SaOS-2. Expressions of IGFBP-6 protein and mRNA increased 2.8 and 2-fold, respectively, in the presence of 17-β-estradiol (E2) (0.01 to 1 μM) and estrogen receptor (ER) in SaOS-2 cells. On the other hand, E2 induced a 2-fold increase in SaOS-2 cell proliferation. To identify genomic sequences associated with estrogen responsiveness, the 5'-promoter region (-44 to +118) of the IGFBP-6 gene was cloned into a chloramphenicol acetyltransferase (CAT) reporter vector. E2 induced a 3-fold increase in CAT activity in SaOS-2 cells transiently transfected with this construct. Identification of the estrogen- responsive element (ERE) [5'-CCTTCA CCTG-3'] (-9 to +1) in this IGFBP-6 gene promoter region was confirmed using electromobility shift assays and deletion analysis. This functional ERE was important for E2-induced trans-activation of the IGFBP-6 gene. These results demonstrate that E2 exhibits a positive effect on IGFBP-6 gene transcription through estrogen- liganded ER binding to the functional ERE in the IGFBP-6 gene promoter in SaOS-2 cells. Osteoblasts can synthesize the insulin-like growth factors (IGFs) and the IGF-binding proteins (IGFBPs), which may either enhance or attenuate IGF-stimulated bone cell proliferation. Since estrogen induced osteoblastic differentiation and proliferation through an estrogen- responsive gene in target cells, we investigated the effects of estrogen on IGFBP-6 expression in the human osteoblastic-like cell line SaOS-2. Expressions of IGFBP-6 protein and mRNA increased 2.8 and 2-fold, respectively, in the presence of 17-β-estradiol (E2) (0.01 to 1 μM) and estrogen receptor (ER) in SaOS-2 cells. On the other hand, E2 induced a 2-fold increase in SaOS-2 cell proliferation. To identify genomic sequences associated with estrogen responsiveness, the 5'-promoter region (-44 to +118) of the IGFBP-6 gene was cloned into a chloramphenicol acetyltransferase (CAT) reporter vector. E2 induced a 3-fold increase in CAT activity in SaOS-2 cells transiently transfected with this construct. Identification of the estrogen- responsive element (ERE) [5'-CCTTCA CCTG-3'] (-9 to +1) in this IGFBP-6 gene promoter region was confirmed using electromobility shift assays and deletion analysis. This functional ERE was important for E2-induced trans-activation of the IGFBP-6 gene. These results demonstrate that E2 exhibits a positive effect on IGFBP-6 gene transcription through estrogen- liganded ER binding to the functional ERE in the IGFBP-6 gene promoter in SaOS-2 cells.

The Relationship Between Preoperative Cervical Sagittal Balance and Clinical Outcome of Patients With Hirayama Disease Treated With Anterior Cervical Discectomy and Fusion

Xiao Lu,Guang-Yu Xu,Cong Nie,Yu Xuan Zhang,Jian Song,Jianyuan Jiang 대한척추신경외과학회 2021 Neurospine Vol.18 No.3

Objective: Anterior cervical discectomy and fusion (ACDF) is a common surgical method used to treat patients with Hirayama disease. And sagittal balance indexes have been revealed to be predictors of clinical outcomes in patients with cervical diseases, but their relationships with ACDF-treated Hirayama disease outcomes remain unknown. The purpose of this study is to evaluate the relationship of preoperative cervical sagittal balance indexes and clinical outcomes in ACDF-treated Hirayama disease patients. Methods: Eighty patients with Hirayama disease treated by ACDF were reviewed retrospectively. Six cervical sagittal balance parameters were collected including Cobb angle, T1 slope, C1–7 sagittal vertical axis (SVA), C2–7 SVA, center of gravity of the head (CGH)-C7 SVA, range of motion. The recovery outcomes of the patients were divided into 2 groups by Odom score and the differences in recovery between the 2 groups were confirmed by electromyography. The correlation between imaging parameters and postoperative outcome was evaluated with logistic regression. The receiver operating characteristic (ROC) curve and area under the ROC curve (AUC) were used to evaluate the significant result of logistic regression and the optimal diagnostic value. Results: Only 2 parameters, Cobb angle and CGH-C7 SVA, showed statistical correlation with the postoperative outcome assessment by logistic regression. AUC of Cobb angle and CGH-C7 SVA were 0.559 and 0.702 respectively. The optimal predictive threshold was 1.50° and 5.40 mm, respectively. Conclusion: A larger Cobb angle and smaller CGH-C7 SVA seemed to correlate with a better postoperative outcome. These 2 factors could be used to predict the outcome of surgical treatment of Hirayama disease preoperatively.

Three Non-Aspartate Amino Acid Mutations in the ComA Response Regulator Receiver Motif Severely Decrease Surfactin Production, Competence Development, and Spore Formation in Bacillus subtilis

( Xiao Yu Wang ),( Chun Ping Luo ),( You Zhou Liu ),( Ya Feng Nie ),( Yong Feng Liu ),( Rong Sheng Zhang ),( Zhi Yi Chen ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.2