Comprehensive Analysis of Magnetization, Magnetostriction, Hysteresis and Kinematical Characteristics for Precision Magnetostrictive Actuator

Hui-Fang Liu,Jie Wang,Han-Yu Wang,Qing-Wei Shao 한국정밀공학회 2016 International Journal of Precision Engineering and Vol.17 No.12

In order to systematically know the operating characteristics and further improve accuracy of precision magnetostrictive actuator used in precision and ultra precision machining fields, a model considering magnetization hysteresis mechanism and kinematics is established based on the domain wall magnetization essential theory. Magnetization, magnetostriction and kinematical characteristics, and the origin of hysteresis are discussed. According to input energy per unit volume of magnetostrictive materials is the sum of static magnetic energy and hysteresis loss energy, magnetization is divided into reversible and irreversible processes. Moreover, hysteresis loop is represented as an offset of irreversible magnetization relative to anhysteretic magnetization. Actuator’s model is deduced through dividing working process into four stages. Experiments show that the predicted values show good agreement with experimental data and average relative error of displacement is less than 5%. Magnetic hysteresis is derived from irreversible process in which magnetic domain cannot return back to initial distribution state completely. And hysteresis is more serious with the increasement of frequency. Research results reveal magnetization and kinematic characteristics from intrinsic physical mechanism, thus it provides a theoretical guidance for further improve the accuracy of magnetostrictive actuator and promotes the practical application of actuator in precision and ultra precision machining fields.

Properties of a CdZnO/ZnO Multiple Quantum-Well Light-Emitting Diode

Zhan-Hui Liu,Li-Li Zhang,Qing-Fang Li,Rong Zhang,Zi-Li Xie,Xiang-Qian Xiu,Bin Liu 한국물리학회 2016 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.69 No.7

A CdZnO/ZnO multiple quantum-well light-emitting diode (LED) structure was successfully grown by using plasma-assisted molecular beam epitaxy on a p-GaN template that had been grown by using metal-organic chemical-vapor deposition on a c-sapphire substrate. The properties of the sample were characterized by using high-resolution X-ray diffraction, transmission electron microscopy, and temperature-dependent photoluminescence measurements. The light output performance of the CdZnO/ZnO QW LED device was also investigated in detail by using I-V and electroluminescence spectral measurements. The characterization showed that our CdZnO/ZnO QW LED structure had good crystalline quality and weaker carrier localization. Owing to the heterojunction structure, the I-V curve indicated that the LED device had a higher turn-on voltage and series resistance. The EL measurement demonstrated that for our LED device’s optoelectronic characteristic, the carrier-screening effect played the dominant role in the emission-energy blue-shift mechanism, and the broadening of the emission energy width was mainly ascribed to the band-filling effect. Without a special heat sinking, the L-I curve exhibited slight efficiency droop after 30 mA.

Remarkable impact of steam temperature on ginsenosides transformation from fresh ginseng to red ginseng

Xu, Xin-Fang,Gao, Yan,Xu, Shu-Ya,Liu, Huan,Xue, Xue,Zhang, Ying,Zhang, Hui,Liu, Meng-Nan,Xiong, Hui,Lin, Rui-Chao,Li, Xiang-Ri The Korean Society of Ginseng 2018 Journal of Ginseng Research Vol.42 No.3

Background: Temperature is an essential condition in red ginseng processing. The pharmacological activities of red ginseng under different steam temperatures are significantly different. Methods: In this study, an ultrahigh-performance liquid chromatography quadrupole time-of-flight tandem mass spectrometry was developed to distinguish the red ginseng products that were steamed at high and low temperatures. Multivariate statistical analyses such as principal component analysis and supervised orthogonal partial least squared discrimination analysis were used to determine the influential components of the different samples. Results: The results showed that different steamed red ginseng samples can be identified, and the characteristic components were 20-gluco-ginsenoside Rf, ginsenoside Re, ginsenoside Rg1, and malonyl-ginsenoside Rb1 in red ginseng steamed at low temperature. Meanwhile, the characteristic components in red ginseng steamed at high temperature were 20R-ginsenoside Rs3 and ginsenoside Rs4. Polar ginsenosides were abundant in red ginseng steamed at low temperature, whereas higher levels of less polar ginsenosides were detected in red ginseng steamed at high temperature. Conclusion: This study makes the first time that differences between red ginseng steamed under different temperatures and their ginsenosides transformation have been observed systematically at the chemistry level. The results suggested that the identified chemical markers can be used to illustrate the transformation of ginsenosides in red ginseng processing.

The Effect of Self-Efficacy of Small Business Start-ups in Korea and China on Startup Performance: Focusing on the Mediating Effect of Startup Intention and the Moderating Effect of Digital Transformation

Jin-Sup Jung(Jin-Sup Jung),Hui-Fang Liu(Hui-Fang Liu),Jun Han(Jun Han) The International Academy of Global Business and T 2022 The International Academy of Global Business and T Vol.18 No.6

Purpose - This study is aimed at small business start-ups in Korea and China, and examines the effect of “self-efficacy,” an individual factor that affects the start-up performance of small business owners on “startup intention” and “start-up performance”. In addition, we will also consider the mediating effect of start-up intention and the moderating effect of digital transformation. At present, due to the proliferation of digital technologies and the prolongation of COVID-19, it is difficult for small business start-ups to operate with their existing business models. Therefore, we have focused on “digital transformation” as one of the capabilities they need. We also wanted to know whether digital transformation has a positive moderating effect between start-up intention and start-up performance in small businesses of Korea and China. Design/Methodology/Approach - In existing research, various factors explaining the start-up performance in small business were reviewed. In this study, the self-efficacy of small business start-ups was set as the independent variable and the start-up performance as the dependent variable. In addition, the mediating effect of the start-up intention was examined. As mentioned above, we also tried to look at the moderating effect of digital transformation. After establishing a research model based on the existing research, a survey was conducted for small business start-ups in Korea and China for empirical test, and the results were analyzed. Findings - In the case of small business start-ups in both Koreas and China, most of the relationships among self-efficacy, start-up intention, and start-up performance showed the same results. On the other hand, in the case of the moderating effect of digital transformation, positive moderating effect was found in Korea. However, there was no moderating effect in China. Research Implications - In both samples from Korea and China, self-efficacy had a positive effect on startup performance through start-up intention. It is inferred that the difference in the moderating effect is due to various factors such as culture, institutions, and policies between Korea and China. Finally, academic, economic, and policy implications were suggested.

Involvement of Orai1 in tunicamycin-induced endothelial dysfunction

Hui Yang,Yumei Xue,Sujuan Kuang,Mengzhen Zhang,Jinghui Chen,Lin Liu,Zhixin Shan,Qiuxiong Lin,Xiaohong Li,Min Yang,Hui Zhou,Fang Rao,Chunyu Deng 대한약리학회 2019 The Korean Journal of Physiology & Pharmacology Vol.23 No.2

Endoplasmic reticulum (ER) stress is mediated by disturbance of Ca2+ homeostasis. The store-operated calcium (SOC) channel is the primary Ca2+ channel in non-excitable cells, but its participation in agent-induced ER stress is not clear. In this study, the effects of tunicamycin on Ca2+ influx in human umbilical vein endothelial cells (HUVECs) were observed with the fluorescent probe Fluo-4 AM. The effect of tunicamycin on the expression of the unfolded protein response (UPR)-related proteins BiP and CHOP was assayed by western blotting with or without inhibition of Orai1. Tunicamycin induced endothelial dysfunction by activating ER stress. Orai1 expression and the influx of extracellular Ca2+ in HUVECs were both upregulated during ER stress. The SOC channel inhibitor SKF96365 reversed tunicamycin-induced endothelial cell dysfunction by inhibiting ER stress. Regulation of tunicamycin-induced ER stress by Orai1 indicates that modification of Orai1 activity may have therapeutic value for conditions with ER stress-induced endothelial dysfunction.

Hydrogen sulfide inhibits the growth of Escherichia coli through oxidative damage

Liu-Hui Fu,Zeng-Zheng Wei,Kang-Di Hu,Lan-Ying Hu,Yan-Hong Li,Xiao-Yan Chen,Zhuo Han,Gai-Fang Yao,Hua Zhang 한국미생물학회 2018 The journal of microbiology Vol.56 No.4

Many studies have shown that hydrogen sulfide (H2S) is both detrimental and beneficial to animals and plants, whereas its effect on bacteria is not fully understood. Here, we report that H2S, released by sodium hydrosulfide (NaHS), significantly inhibits the growth of Escherichia coli in a dose-dependent manner. Further studies have shown that H2S treatment stimulates the production of reactive oxygen species (ROS) and decreases glutathione (GSH) levels in E. coli, resulting in lipid peroxidation and DNA damage. H2S also inhibits the antioxidative enzyme activities of superoxide dismutase (SOD), catalase (CAT) and glutathione reductase (GR) and induces the response of the SoxRS and OxyR regulons in E. coli. Moreover, pretreatment with the antioxidant ascorbic acid (AsA) could effectively prevent H2S-induced toxicity in E. coli. Taken together, our results indicate that H2S exhibits an antibacterial effect on E. coli through oxidative damage and suggest a possible application for H2S in water and food processing.

Relationship Between Computed Tomography Manifestations of Thymic Epithelial Tumors and the WHO Pathological Classification

Liu, Guo-Bing,Qu, Yan-Juan,Liao, Mei-Yan,Hu, Hui-Juan,Yang, Gui-Fang,Zhou, Su-Jun Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.11

Objective: To explore the relationship between computed tomography (CT) manifestations of thymoma and its WHO pathological classification. Methods: One hundred and five histopathologically confirmed cases were collected for their pathological and CT characteristics and results were statistically compared between different pathological types of thymoma. Results: Tumor size, shape, necrosis or cystic change, capsule integrity, invasion to the adjacent tissue, lymphadenopathy, and the presence of pleural effusion were significantly different between different pathological types of thymomas (P<0.05). Type B2, B3 tumors and thymic carcinomas were greater in size than other types. More than 50% of type B3 tumors and thymic carcinomas had a tumor size greater than 10 cm. The shape of types A, AB, and B1 tumors were mostly round or oval, whereas 75% of type B3 tumors and 85% of thymic carcinomas were irregular in shape. Necrosis or cystic change occurred in 67% of type B3 thymomas and 57% of thymic carcinomas, respectively. The respective figures for capsule destruction were 83% and 100%. Increases in the degree of malignancy were associated with increases in the incidence of surrounding tissue invasion: 33%, 75%, and 81% in type B2, type B3, and thymic carcinomas, respectively. Pleural effusion occurred in 48% of thymic carcinomas, while calcification was observed mostly in type B thymomas. Conclusions: Different pathological types of thymic epithelial tumors have different CT manifestations. Distinctive CT features of thymomas may reflect their pathological types.

Exogenous p53 Upregulated Modulator of Apoptosis (PUMA) Decreases Growth of Lung Cancer A549 Cells

Liu, Chun-Ju,Zhang, Xia-Li,Luo, Da-Ya,Zhu, Wei-Feng,Wan, Hui-Fang,Yang, Jun-Ping,Yang, Xiao-Jun,Wan, Fu-Sheng Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.2

Purpose: To investigate the influence of exogenous p53 upregulated modulator of apoptosis (PUMA) expression on cell proliferation and apoptosis in human non-small cell lung cancer A549 cells and transplanted tumor cell growth in nude mice. Materials and Methods: A549 cells were divided into the following groups: control, non-carrier (NC), PUMA (transfected with pCEP4-(HA) 2-PUMA plasmid), DDP ($10{\mu}g/mL$ cisplatin treatment) and PUMA+DDP (transfected with pCEP4-(HA)2-PUMA plasmid and $10{\mu}g/mL$ cisplatin treatment). The MTT method was used to detect the cell survival rate. Cell apoptosis rates were measured by flow cytometry, and PUMA, Bax and Bcl-2 protein expression levels were measured by Western blotting. Results: Compared to the control group, the PUMA, DDP and PUMA+DDP groups all had significantly decreased A549 cell proliferation (p<0.01), with the largest reduction in the PUMA+DDP group. Conversely, the apoptosis rates of the three groups were significantly increased (P<0.01), and the PUMA and DDP treatments were synergistic. Moreover, Bax protein levels significantly increased (p<0.01), while Bcl-2 protein levels significantly decreased (p<0.01). Finally, both the volume and the weights of transplanted tumors were significantly reduced (p<0.01), and the inhibition ratio of the PUMA+DDP group was significantly higher than in the single DDP or PUMA groups. Conclusions: Exogenous PUMA effectively inhibited lung cancer A549 cell proliferation and transplanted tumor growth by increasing Bax protein levels and reducing Bcl-2 protein levels.

Influence of dragon bamboo with different planting patterns on microbial community and physicochemical property of soil on sunny and shady slopes

Liu Weiyi,Wang Fang,Sun Yanmei,Yang Lei,Chen Huihai,Liu Weijie,Zhu Bin,Hui Chaomao,Wang Shiwei 한국미생물학회 2020 The journal of microbiology Vol.58 No.11

Dragon bamboo (Dendrocalamus giganteus) is a giant sympodial bamboo species widely distributed in Asia. However, it remains unclear how dragon bamboo and soil microbes interact to affect soil properties. In this study, we investigated the planting patterns (semi-natural and artificial) on different slopes (sunny and shady) to determine the effects on soil properties and microbial community. The results showed that the soil in which dragon bamboo was grown was acidic, with a pH value of ~5. Also, the soil organic matter content, nitrogen hydrolysate concentration, total nitrogen, available potassium, and total potassium of the dragon bamboo seminatural forest significantly improved, especially on the sunny slope. In contrast, the available phosphorus level was higher in the artificial bamboo forest, probably owing to the phosphate fertilizer application. The bacterial and fungal diversity and the bacterial abundance were all higher on the sunny slope of the semi-natural forest than those in the other samples. The microbial operational taxonomic units (OTUs) shared between the shady and sunny slopes accounted for 47.8–62.2%, but the core OTUs of all samples were only 24.4– 30.4% of each sample, suggesting that the slope type had a significant effect on the microbial community. Some acidophilic microbes, such as Acidobacteria groups, Streptomyces and Mortierella, became dominant in dragon bamboo forest soil. A PICRUSt analysis of the bacterial functional groups revealed that post-translational modification, cell division, and coenzyme transport and metabolism were abundant in the semi-natural forest. However, some microorganisms with strong stress resistance might be activated in the artificial forest. Taken together, these results illustrated the influence of dragon bamboo growth on soil physicochemical property and microbial community, which might help understand the growth status of dragon bamboo under different planting patterns.

Single-cell RNA sequencing reveals B cell–related molecular biomarkers for Alzheimer’s disease

Xiong Liu-Lin,Xue Lu-Lu,Du Ruo-Lan,Niu Rui-Ze,Chen Li,Chen Jie,Hu Qiao,Tan Ya-Xin,Shang Hui-Fang,Liu Jia,Yu Chang-Yin,Wang Ting-Hua 생화학분자생물학회 2021 Experimental and molecular medicine Vol.53 No.-

In recent years, biomarkers have been integrated into the diagnostic process and have become increasingly indispensable for obtaining knowledge of the neurodegenerative processes in Alzheimer’s disease (AD). Peripheral blood mononuclear cells (PBMCs) in human blood have been reported to participate in a variety of neurodegenerative activities. Here, a single-cell RNA sequencing analysis of PBMCs from 4 AD patients (2 in the early stage, 2 in the late stage) and 2 normal controls was performed to explore the differential cell subpopulations in PBMCs of AD patients. A significant decrease in B cells was detected in the blood of AD patients. Furthermore, we further examined PBMCs from 43 AD patients and 41 normal subjects by fluorescence activated cell sorting (FACS), and combined with correlation analysis, we found that the reduction in B cells was closely correlated with the patients’ Clinical Dementia Rating (CDR) scores. To confirm the role of B cells in AD progression, functional experiments were performed in early-stage AD mice in which fibrous plaques were beginning to appear; the results demonstrated that B cell depletion in the early stage of AD markedly accelerated and aggravated cognitive dysfunction and augmented the Aβ burden in AD mice. Importantly, the experiments revealed 18 genes that were specifically upregulated and 7 genes that were specifically downregulated in B cells as the disease progressed, and several of these genes exhibited close correlation with AD. These findings identified possible B cell-based AD severity, which are anticipated to be conducive to the clinical identification of AD progression.