Antioxidant Action of a Chrysanthemum morifolium Extract Protects Rat Brain Against Ischemia and Reperfusion Injury

Guo-Hua Lin,Lin Lin,Hua-Wei Liang,Xin Ma,Jing-Ye Wang,Li-Ping Wu,Hui-Di Jiang,Iain C. Bruce,Qiang Xia 한국식품영양과학회 2010 Journal of medicinal food Vol.13 No.2

The present study evaluated the potential neuroprotective effect and underlying mechanism of the total flavones extracted from Chrysanthemum morifolium (TFCM) against ischemia/reperfusion (I/R) injury. An animal model of cerebral ischemia was established by occluding the right middle cerebral artery for 90 minutes followed by reperfusion for 22 hours. The neurobehavioral scores, infarct area, and hemispheric edema were evaluated. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, and reactive oxygen species (ROS) level in brain were also measured. The results showed that pretreatment with TFCM significantly decreased the neurological deficit scores, percentage of infarction, and brain edema and attenuated the decrease in SOD activity, the elevation of MDA content, and the generation of ROS. In isolated brain mitochondria, Ca2+-induced swelling was attenuated by pretreatment with TFCM, and this effect was antagonized by atractyloside. These results showed that pretreatment with TFCM provides significant protection against cerebral I/R injury in rats by, at least in part, its antioxidant action and consequent inhibition of mitochondrial swelling.

Application of Near Spectroscopy for Nondestructive Evaluation of Ginsenoside Content

Lin, Guo-Lin,Cho, Rae-Kwang,Hong, Jin-Hwan 한국근적외분광분석학회 2000 Near infrared analysis Vol.1 No.2

The effective component Ginsenoside in Ginseng has been widely used to cure some hypochondriasis and be as supplementary medicines. There are many chemical analysis methods to measure the contents of Ginsenoside in Ginseng; however, all these methods have some shortcomings such as long time, environmental pollution and damaging the samples. In this paper, it is possible to use near infrared spectroscopy to measure the content of Ginsenoside in Ginseng without destruction. As the results, Rg1, Rb1, Re and T-Saponin of Ginsenoside can be measured with the accuracy of R(0.81) SEP (1.704 mg/g), R(0.74) SEP (1.211 mg/g), R (0.78) SEP (1.049 mg/g) and R(0.84), SEP(4.537 mg/g).

Discrimination of geographical origin and cultivation years of Ginseng by near Infrared reflectance spectroscopy

Lin, Guo-Lin,Sohn, Mi-Ryeong,Cho, Rae-Kwnag,Hong, Jin-Hwan 한국근적외분광분석학회 2000 Near infrared analysis Vol.1 No.2

The objectives of this study are to discriminate the geographical origin and cultivation years of ginseng based on the near-infrared(NIR) reflectance spectroscopic analysis. Korea and China ginseng samples were prepared for discrimination of geographical origin. 4, 5 and 6 years-old ginseng samples from Korea were prepared for discrimination of cultivation years. Used spectrometer were InfraAlyzer 500, InfraAlyzer 400 and Fiber optic. Sample type of ginseng was 3, whole ginseng radix, slide section and powder type. The accuracy was affected by sample types and instruments. The accuracy for discrimination geographical origin was 97% in calibration model using IA 500 and ginseng powder. For discrimination of cultivation years, the model with slide selection using IA500 were relative accurate. The accuracy was 96.7% for 4-year, 91.3% for 5-year and 89.3% for 6-year old ginseng. The study shows that NIR spectroscopic analysis can be used to discriminate the geographical origin and cultivation years of ginseng with acceptable accuracy.

Effect of using ink containing polyacrylate and silicone surfactant on the inkjet printing of quantum dot films

Lin Nan,Ye Yun,Guo Qian,Yu Jinhui,Guo Tailiang 한국정보디스플레이학회 2020 Journal of information display Vol.21 No.2

For device printing, it is important for uniform films to be printed because the morphology of the film affects the performance of the device in inkjet printing. In this study, to prepare stable and well-dispersed ink, polyacrylate and silicone surfactant BD-3033H were added to ink. Then a uniform quantum dot (QD) film was obtained by optimizing the polyacrylate and silicone surfactant contents of the ink as well as the substrate temperature. The change of the polyacrylate structure from a curly chain structure to a three-dimensional network structure blocked the outward flow of QDs. Silicone surfactant BD-3033H caused Marangoni flow and made the QDs flow inward. When the substrate temperature was increased, the solvent evaporation rate was accelerated, the contact line was pinned, and the outward flow was enhanced, which changed the film structure from convex to flat. Finally, when the polyacrylate content was 12 wt%, the silicone surfactant BD-3033H content was 0.10 wt%, the substrate temperature was 40°C, and the coffee ring effect was eliminated. A uniform QD film was printed, providing a technical guarantee for the fabrication of QD devices in the future.

An Enhanced Power Sharing Strategy for Islanded Microgrids Considering Impedance Matching for Both Real and Reactive Power

Lin, Liaoyuan,Guo, Qian,Bai, Zhihong,Ma, Hao The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

There exists a strong coupling between real and reactive power owing to the complex impedances in droop based islanded microgrids (MGs). The existing virtual impedance methods consider improvements of the impedance matching for sharing of the voltage controlled power (VCP) (reactive power for Q-V droop, and real power for P-V droop), which yields a 1-DOF (degree of freedom) tunable virtual impedance. However, a weak impedance matching for sharing of the frequency controlled power (FCP) (real power for $P-{\omega}$ droop, and reactive power for $Q-{\omega}$ droop) may result in FCP overshoots and even oscillations during load transients. This in turn results in VCP oscillations due to the strong coupling. In this paper, a 2-DOF tunable adaptive virtual impedance method considering impedance matching for both real and reactive power (IM-PQ) is proposed to improve the power sharing performance of MGs. The dynamic response is promoted by suppressing the coupled power oscillations and power overshoots while realizing accurate power sharing. In addition, the proposed power sharing controller has a better parametric adaptability. The stability and dynamic performances are analyzed with a small-signal state-space model. Simulation and experimental results are presented to investigate the validity of the proposed scheme.

Unilateral ureteral obstruction causes gut microbial dysbiosis and metabolome disorders contributing to tubulointerstitial fibrosis

Lin Chen,Dan-Qian Chen,Jing-Ru Liu,Jun Zhang,Nosratola D. Vaziri,Shougang Zhuang,Hua Chen,Ya-Long Feng,Yan Guo,Ying-Yong Zhao 생화학분자생물학회 2019 Experimental and molecular medicine Vol.51 No.-

Chronic kidney disease (CKD) increases the risk and prevalence of cardiovascular disease (CVD) morbidity and mortality. Recent studies have revealed marked changes in the composition of the microbiome and the metabolome and their potential influence in renal disease and CVD via the accumulation of microbial-derived uremic toxins. However, the effect of unilateral ureteral obstruction (UUO) on the gut microbiome and circulating metabolites is unknown. Male Sprague-Dawley rats were randomized to UUO and sham-operated control groups. Renal histology, colonic microbiota, and plasma metabolites were examined two weeks later. We employed 16S rRNA sequence and untargeted metabolomic analyses to explore the changes in colonic microbiota and plasma metabolites and their relationship with tubulointerstitial fibrosis (TIF). The UUO rats exhibited tubular atrophy and dilatation, interstitial fibrosis and inflammatory cell infiltration in the obstructed kidney. UUO rats showed significant colonic enrichment and depletion of genera. Significant differences were identified in 219 plasma metabolites involved in lipid, amino acid, and bile acid metabolism, which were consistent with gut microbiota-related metabolism. Interestingly, tryptophan and its metabolites kynurenine, 5-hydroxytryptophan and 5-hydroxytryptamine levels, which were linked with TIF, correlated with nine specific genera. Plasma tryptophan level was positively correlated with Clostridium IV, Turicibacter, Pseudomonas and Lactobacillales, and negatively correlated with Oscillibacter, Blautia, and Intestinimonas, which possess the genes encoding tryptophan synthase (K16187), indoleamine 2,3-dioxygenase (K00463) and tryptophan 2,3-dioxygenase (K00453) and their corresponding enzymes (EC:1.13.11.52 and EC:1.13.11.11) that exacerbate TIF. In conclusion, UUO results in profound changes in the gut microbiome and circulating metabolites, events that contribute to the pathogenesis of inflammation and TIF.

Overexpression of StNHX1, a Novel Vacuolar Na+/H+ Antiporter Gene from Solanum torvum, Enhances Salt Tolerance in Transgenic Vegetable Soybean

Guo-Hu Chen,Wenyan Wang,Li-Fei Yang,Jun-Yi Gai,Yue-Lin Zhu 한국원예학회 2014 Horticulture, Environment, and Biotechnology Vol.55 No.3

Soil salinity is the primary limiting factor affecting the growth and production of vegetable soybean[Glycine max (L.) Merrill] worldwide. Plants can survive in salinity conditions through the mechanism of sodium ion(Na+) compartmentalization, during which the vacuolar Na+/H+ antiporter (NHX) genes play a critical role. In the presentstudy, a novel vacuolar NHX gene from Solanum torvum Swartz ‘Torvum Vigor’ (StNHX1; GenBank accessionnumber: JN606860.1) was isolated and transferred into the vegetable soybean ‘Xinliaoxian’ through an Agrobacteriummediatedprotocol. The PCR and southern blot analyses confirmed the successful integration of the exogenous genes. The GUS assay and semi-quantitative RT-PCR analysis showed that the alien genes were inherited by the progeniesand that the StNHX1 gene was overexpressed in the T3 generation. The overexpression of this gene conferred hightolerance to salt stress. Under 100 mM NaCl conditions, the scorch scores and the Na+ and malondialdehyde (MDA)contents of the leaves of the transgenic lines were significantly lower as compared with the wild-type (WT) plants,while the K+/Na+ ratio, the contents of K+, relative chlorophyll and relative water, and some morphological traits of thetransgenic plants were significantly higher than those of the WT. These results indicate that the overexpression ofStNHX1 enhances the salt tolerance of vegetable soybean and that StNHX1 is one of the promising target genes thatcan be manipulated to improve the salinity tolerance of crops.

Theoretical research on the identification method of bridge dynamic parameters using free decay response

Guo-jin Tan,Yong-chun Cheng,Han-bing Liu,Long-lin Wang 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.38 No.3

Input excitation and output response of structure are needed in conventional modal analysis methods. However, input excitation is often difficult to be obtained in the dynamic load test of bridge structures. Therefore, what attracts engineers’ attention is how to get dynamic parameters from the output response. In this paper, a structural experimental modal analysis method is introduced, which can be used to conveniently obtain dynamic parameters of the structure from the free decay response. With known damping coefficients, this analysis method can be used to identify the natural frequencies and the mode shapes of MDOF structures. Based on the modal analysis theory, the mathematical relationship of damping ratio and frequency is obtained. By using this mathematical relationship to improve the previous method, an improved experimental modal analysis method is proposed in this paper. This improved method can overcome the deficiencies of the previous method, which can not identify damping ratios and requires damping coefficients in advance. Additionally, this improved method can also identify the natural frequencies, mode shapes and damping ratios of the bridge only from the free decay response, and ensure the stability of identification process by using modern mathematical means. Finally, the feasibility and effectiveness of this method are demonstrated by a numerical example of a simply supported reinforced concrete beam.

A STABILITY RESULT FOR P-CENTROID BODIES

Guo, Lujun,Leng, Gangsong,Lin, Youjiang Korean Mathematical Society 2018 대한수학회보 Vol.55 No.1

In this paper, we prove a stability result for p-centroid bodies with respect to the Hausdorff distance. As its application, we show that the symmetric convex body is determined by its p-centroid body.

A Duplicate Address Resolution Protocol in Mobile Ad Hoc Networks

Lin Chunhung Richard,Wang Guo-Yuan Mikko The Korea Institute of Information and Commucation 2005 Journal of communications and networks Vol.7 No.4

In an IP-based network, automated dynamic assignment of IP addresses is preferable. In most wired networks, a node relies on a centralized server by using dynamic host configuration protocol (DHCP) to obtain a dynamic IP address. However, the DHCP­based approach cannot be employed in a mobile ad hoc network (MANET) due to the uncertainty of any centralized DHCP server. That is, a MANET may become partitioned due to host mobility. Therefore, there is no guarantee to access a DHCP server. A general approach to address this issue is to allow a mobile host to pick a tentative address randomly, and then use duplicate address resolution (DAR) protocol to resolve any duplicate addresses. In this paper, an innovative distributed dynamic host configuration protocol designed to configure nodes in MANET is presented. The proposed protocol not only can detect the duplicate address, but also can resolve the problem caused by duplicate address. It shows that the proposed protocol works correctly and is more universal than earlier approaches. An enhanced version of DAR scheme is also proposed in this paper to solve the situation of duplicate MAC address. The new and innovative approach proposed in this paper can make the nodes in MANET provide services to other networks and avoid packets from being delivered to incorrect destinations.