In SR-GIXRD Study of Oxide Film Evaluation on AISI 304 Stainless Steel in High Temperature Water

Yan Zhao,Jianjun Guan,Feng Liu,Ping Liang,Congqian Cheng,Jie Zhao 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.5

Oxide films on AISI 304 stainless steel in high temperature and high pressure water were detected by a new method thatsynchrotron radiation grazing incidence X-ray diffraction. The morphology, phase structure, thickness and electrochemicalcorrosion resistance of the oxide films were illustrated. A empirical equation for oxide growth is applied to evaluate thechanges in film thickness. Observations suggest that small irregular granular (Fe, Cr)2O3 oxides and polyhedral block (Fe,Cr)3O4 oxides are grown on stainless steel surface. The fine inner (Fe, Cr)2O3 particles preferentially form, and the part isprecipitated by the (Fe, Cr)3O4 structure for the diffusion outward, leading to the formation of external coarse grain oxides. The average size of (Fe, Cr)2O3 is slightly oscillated with the oxidation time, and that of (Fe, Cr)3O4 oxides increases withthe increasing exposure time. The oxide film thickness is less than 500 nm for 24 h oxidation in high temperature water, andfor 240 h oxidation the thickness is less than 800 nm. Polarization and EIS test results indicate that the oxide films of (Fe,Cr)2O3 and (Fe, Cr)3O4 provides corrosion resistance for stainless steel.

Output Feedback Stabilization for an ODE Coupled with a Wave Equation with Variable Coefficients

Yan Xing Zhao,Jun Jun Liu,Yan Na Jia 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.2

In this paper, we are concerned with the output feedback problem for coupled ODE-wave systems subject to spatially-varying coefficients. An original transformation is designed to turn the wave equation into an equation of the same type with constant coefficient and low order term. Taking advantage of the backstepping method, a state observer is constructed by non-collocated boundary displacement and velocity measurement. Output feedback on the based of the observer output feedback is then constructed, which makes use of the backstepping method to make the system exponentially stable. Finally, we demonstrate the well-posed and the exponential stability of the closed-loop system.

Effect of alfalfa habitat change on dispersal behavior of Harmonia axyridis Pallas and Hippodamia variegata Goeze (Coleoptera: Coccinellidae)

Liu JunHe,Zhao Zhong,Yan Yan,Ali Abid,Ahmed Zeeshan,He DaHan,Yu Mingfu,Hang Jia,Perven Misbah,Nazir Tamsila,Tayyib Muhammad,Zhao ZiHua 한국응용곤충학회 2021 Journal of Asia-Pacific Entomology Vol.24 No.4

An alfalfa grassland landscape was divided into 36 plots during 2014 season in Yuanzhou District of Guyuan city in Ningxia Hui Autonomous Region of P.R. China. In these three times repeated experiments, treatment of habitat fragmentation was divided into two grades: continuity (H = 0.0) and fragmentation (H = 1.0), and their habitat loss rate was divided into 6 grades: 90, 80, 70, 50, 20 and 0%. Considering habitat loss 0% of the plot as the reference, as a result of sweeping net and visual methods, results showed that the flight distance of the Harmonia axyridis was much higher than that of the Hippodamia variegata both in fragmentation and continuous habitats. In the alfalfa landscape, H. axyridis moved more by flying, while H. variegata moved more by crawling. There was a threshold effect that affected the movement behavior of lady beetles between 70 and 100% of the habitat loss. The population of the two species of lady beetles in the continuous habitat was higher than that in the habitat fragmentation and was more obvious in 70 and 50% plots of the habitat loss. The dispersal rate of the two species of lady beetles inside plots was higher than outside of the experimental plots, which reflected the low diffusivity of the ladybeetle. Habitat fragmentation affected the dispersal, migration and construction of two species of lady beetles on different spatial scales by disturbing the spread of natural enemies and searching for prey.

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.

Cadmium induces apoptosis in primary rat osteoblasts through caspase and mitogen-activated protein kinase pathways

Hong-Yan Zhao,Wei Liu,Yi Wang,Nannan Dai,Jian-Hong Gu,Yan Yuan,Xue-Zhong Liu,Jian-Chun Bian,Zong-Ping Liu 대한수의학회 2015 Journal of Veterinary Science Vol.16 No.3

Exposure to cadmium (Cd) induces apoptosis in osteoblasts (OBs); however, little information is available regarding the specific mechanismsof Cd-induced primary rat OB apoptosis. In this study, Cd reduced cell viability, damaged cell membranes and induced apoptosis in OBs. We observed decreased mitochondrial transmembrane potentials, ultrastructure collapse, enhanced caspase-3 activity, and increasedconcentrations of cleaved PARP, cleaved caspase-9 and cleaved caspase-3 following Cd treatment. Cd also increased the phosphorylationof p38-mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinases (ERK)1/2 and c-jun N-terminal kinase (JNK) in OBs. Pretreatment with the caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, ERK1/2 inhibitor (U0126), p38 inhibitor(SB203580) and JNK inhibitor (SP600125) abrogated Cd-induced cell apoptosis. Furthermore, Cd-treated OBs exhibited signs of oxidativestress protection, including increased antioxidant enzymes superoxide dismutase and glutathione reductase levels and decreased formationof reactive oxygen species. Taken together, the results of our study clarified that Cd has direct cytotoxic effects on OBs, which are mediatedby caspase- and MAPK pathways in Cd-induced apoptosis of OBs.

A Rapidly New-typed Detection of Norovirus Based on F0F1-ATPase Molecular Motor Biosensor

Zhuo Zhao,Jie Zhang,Mei-Ling Xu,Zhi-Peng Liu,Hua Wang,Ming Liu,Yan-Yan Yu,Li Sun,Hui Zhang,Hai-Yan Wu 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.1

In order to adapt port rapid detection of food borne norovirus, presently we developed a new typed detection method based on F0F1-ATPase molecular motor biosensor. A specific probe was encompassed the conservative region of norovirus and F0F1-ATPase within chromatophore was constructed as a molecular motor biosensor through the “ε-subunit antibody-streptomycinbiotin- probe” system. Norovirus was captured based on probe-RNA specific binding. Our results demonstrated that the Limit of Quantification (LOQ) is 0.005 ng/mL for NV RNA and also demonstrated that this method possesses specificity and none cross-reaction for food borne virus. What’s more, the experiment used this method could be accomplished in 1 h. We detected 10 samples by using this method and the results were consistent with RT-PCR results. Overall, based on F0F1-ATPase molecular motors biosensor system we firstly established a new typed detection method for norovirus detection and demonstrated that this method is sensitive and specific and can be used in the rapid detection for food borne virus.

Activation of the wnt/β-Catenin Signaling Pathway in Polymyositis, Dermatomyositis and Duchenne Muscular Dystrophy

Fuchen Liu,Zonglai Liang,Jingwen Xu,Wei Liu,Dandan Zhao,Yuying Zhao,Chuanzhu Yan 대한신경과학회 2016 Journal of Clinical Neurology Vol.12 No.3

Background and PurposezzTe wnt/β-catenin signaling pathway plays a critical role in embryonic development and adult-tissue homeostasis. Recent investigations implicate the importance of wnt/β-catenin signaling in normal wound healing and its sustained activation being associated with fbrogenesis. We investigated the immunolocalization and activation of wnt/β-catenin in polymyositis (PM), dermatomyositis (DM), and Duchenne muscular dystrophy (DMD). MethodszzImmunofuorescence staining and Western blot analysis of β-catenin were performed in muscle specimens from 6 PM, 8 DM, and 6 DMD subjects. Te β-catenin/Tcf4 DNA-binding activity in muscle was studied using an electrophoretic mobility shif assay (EMSA), and serum wnt/β-catenin/Tcf transcriptional activity was measured using a luciferase reporter gene assay. ResultszzImmunoreactivity for β-catenin was found in the cytoplasm and nuclei of muscle fbers in PM, DM, and DMD. Te protein level of β-catenin was elevated, and EMSA analysis confrmed the activation of wnt/β-catenin signaling. Te transcriptional activities of β-catenin/ Tcf in the circulation were increased in patients with PM, DM, and DMD, especially in those with interstitial lung disease, and these transcriptional activities decreased when PM or DM patients exhibited obvious clinical improvements. ConclusionszzOur fndings indicate that wnt/β-catenin signaling is activated in PM, DM, and DMD. Its activation in muscle tissue and the circulation may play a role in modulating muscle regeneration and be at least partly involved in the process of muscle and pulmonary fbrosis.

Structural and Ferromagnetic Properties SnO2/TiO2 Nanotubes Obtained by Electrospinning

JIAN-GUO ZHAO,Yan-Hong Gu,Hong Jia,Zhuan Hu,Shuqian Qiao,Mengjing Jin,Panting Ge,WEI-YING ZHANG,Shijiang Liu,ZHAO-JUN LIU 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2017 NANO Vol.12 No.10

SnO2/TiO2 (Sn/Ti = 5/1) nanotubes were prepared by the electrospinning method. The morphology was characterized by scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the inner diameter of prepared materials was about 100 nm and the wall thickness was about 10 nm. The results of X-ray diffraction (XRD) and high resolution transmission electron microscope (HRTEM) showed that SnO2/TiO2 nanotubes had a mixed phase of SnO2 rutile and TiO2 anatase structures and no impurity phases. The magnetic properties of the SnO2/TiO2 nanotubes were characterized by a superconducting quantum interferometer (SQUID). The results indicated that the samples exhibited room temperature ferromagnetism which may be attributed to the interface between TiO2 and SnO2 phases.

The New Strategy of Object-Based Directional Query

Run-tao liu,Yan-ming Wang,Zhen-guo Zhao,Guang -Yue Tian 보안공학연구지원센터 2014 International Journal of Database Theory and Appli Vol.7 No.6

To increase directional query efficiency, based on the study of existing algorithms of directional query, new pruning rules for directional query were given, combined with the new index structure MB-tree. The rules exclude the MBRs outside the query area and output all leaf nodes in the MBRs inside the query area. Based on the orders defined in MB-tree, a new algorithm of directional query is given combining with MB-tree by using recursive method, and the new algorithm can reduce I/O cost effectively. Experiment showed that the new directional query algorithm reduces the number of visited nodes, decreases I/O cost, and improves the efficiency of directional query.

Association between Initial Chest CT or Clinical Features and Clinical Course in Patients with Coronavirus Disease 2019 Pneumonia

Liu Zhe,Jin Chao,Wu Carol C.,Liang Ting,Zhao Huifang,Wang Yan,Wang Zekun,Li Fen,Zhou Jie,Cai Shubo,Zeng Lingxia,Yang Jian 대한영상의학회 2020 Korean Journal of Radiology Vol.21 No.6

Objective: To identify the initial chest computed tomography (CT) findings and clinical characteristics associated with the course of coronavirus disease 2019 (COVID-19) pneumonia. Materials and Methods: Baseline CT scans and clinical and laboratory data of 72 patients admitted with COVID-19 pneumonia (39 men, 46.2 ± 15.9 years) were retrospectively analyzed. Baseline CT findings including lobar distribution, presence of ground glass opacities, consolidation, linear opacities, and lung severity score were evaluated. The outcome event was recovery with hospital discharge. The time from symptom onset to discharge or the end of follow-up (for those remained hospitalized) was recorded. Data were censored in events such as death or discharge without recovery. Multivariable Cox proportional hazard regression was used to explore the association between initial CT, clinical or laboratory findings, and discharge with recovery, whereby hazard ratio (HR) values < 1 indicated a lower rate of discharge at four weeks and longer time until discharge. Results: Thirty-two patients recovered and were discharged during the study period with a median length of admission of 16 days (range, 9 to 25 days), while the rest remained hospitalized at the end of this study (median, 17.5 days; range, 4 to 27 days). None died during the study period. After controlling for age, onset time, lesion characteristics, number of lung lobes affected, and bilateral involvement, the lung severity score on baseline CT (> 4 vs. ≤ 4 [reference]: adjusted HR = 0.41 [95% confidence interval, CI = 0.18–0.92], p = 0.031) and initial lymphocyte count (reduced vs. normal or elevated [reference]: adjusted HR = 0.14 [95% CI = 0.03–0.60], p = 0.008) were two significant independent factors that influenced recovery and discharge. Conclusion: Lung severity score > 4 and reduced lymphocyte count at initial evaluation were independently associated with a significantly lower rate of recovery and discharge and extended hospitalization in patients admitted for COVID-19 pneumonia.