Experimental Study on Frequency Support of Variable Speed Wind Turbine Based on Electromagnetic Coupler

Rui You,Jianyun Chai,Xudong Sun,Daqiang Bi,Xinzhen Wu 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1

In the variable speed Wind Turbine based on ElectroMagnetic Coupler (WT-EMC), a synchronous generator is coupled directly to the grid. Therefore, like conventional power plants, WT-EMC is able to inherently support grid frequency. However, due to the reduced inertia of the synchronous generator, WT-EMC is expected to be controlled to increase its output power in response to a grid frequency drop to support grid frequency. Similar to the grid frequency support control of Type 3 or Type 4 wind turbine, inertial control and droop control can be used to calculate the WT-EMC additional output power reference according to the synchronous generator speed. In this paper, an experimental platform is built to study the grid frequency support from WT-EMC with inertial control and droop control. Two synchronous generators, driven by two induction motors controlled by two converters, are used to emulate the synchronous generators in conventional power plants and in WT-EMCs respectively. The effectiveness of the grid frequency support from WT-EMC with inertial control and droop control responding to a grid frequency drop is validated by experimental results. The selection of the grid frequency support controller and its gain for WT-EMC is analyzed briefly.

Experimental Study on Frequency Support of Variable Speed Wind Turbine Based on Electromagnetic Coupler

You, Rui,Chai, Jianyun,Sun, Xudong,Bi, Daqiang,Wu, Xinzhen The Korean Institute of Power Electronics 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.1

In the variable speed Wind Turbine based on ElectroMagnetic Coupler (WT-EMC), a synchronous generator is coupled directly to the grid. Therefore, like conventional power plants, WT-EMC is able to inherently support grid frequency. However, due to the reduced inertia of the synchronous generator, WT-EMC is expected to be controlled to increase its output power in response to a grid frequency drop to support grid frequency. Similar to the grid frequency support control of Type 3 or Type 4 wind turbine, inertial control and droop control can be used to calculate the WT-EMC additional output power reference according to the synchronous generator speed. In this paper, an experimental platform is built to study the grid frequency support from WT-EMC with inertial control and droop control. Two synchronous generators, driven by two induction motors controlled by two converters, are used to emulate the synchronous generators in conventional power plants and in WT-EMCs respectively. The effectiveness of the grid frequency support from WT-EMC with inertial control and droop control responding to a grid frequency drop is validated by experimental results. The selection of the grid frequency support controller and its gain for WT-EMC is analyzed briefly.

Role of active and passive smoking in high-risk human papillomavirus infection and cervical intraepithelial neoplasia grade 2 or worse

Rui-Mei Feng,Shang-Ying Hu,Fang-Hui Zhao,Rong Zhang,Xun Zhang,Asya Izraelit Wallach,You-Lin Qiao 대한부인종양학회 2017 Journal of Gynecologic Oncology Vol.28 No.5

Objective: We performed a pooled analysis to examine cigarette smoking and householdpassive smoke exposure in relation to the risk of human papillomavirus (HPV) infection andcervical intraepithelial neoplasia grade 2+ (CIN2+). Methods: Data were pooled from 12 cross-sectional studies for cervical cancer screeningsfrom 10 provinces of China in 1999–2007. A total of 16,422 women were analyzed, alongwith 2,392 high-risk-HPV (hr-HPV) positive women and 381 CIN2+ cases. Pooled odds ratios(ORs) and 95% confidence intervals (CIs) were estimated using logistic regression modelscontrolling for sexual and non-sexual confounding factors. Results: There was an excess risk between active smoking and hr-HPV infection and CIN2+. Adjusted OR for ever smokers vs. never smokers was 1.45 (95% CI=1.10–1.91), for hr-HPVinfection and 1.89 (95% CI=1.03–3.44), for CIN2+. Passive smoking had a slightly increasedrisk on the hr-HPV infection with adjusted OR 1.11 (1.00–1.24), but no statistical associationwas observed between passive smoke exposure and CIN2+. Compared with the neither activenor passive smokers, both active and passive smokers had a 1.57-fold (95% CI=1.14–2.15)increased risk of HPV infection and a 1.99-fold (95% CI=1.02–3.88) risk of CIN2+. Conclusion: Our large multi-center cross-sectional study found active smoking couldincrease the risk of overall hr-HPV infection and CIN2+ adjusted by passive smoking andother factors. Passive smoking mildly increased the risk of HPV infection but not the CIN2+. An interaction existed between passive tobacco exposure and active smoking for hr-HPVinfection and the CIN2+.

Poster Session : Cytoprotective activity of carpinus tschonoskii against H2O2 induced oxidative stress

( Rui Zhang ),( Kyoung Ah Kang ),( Mei Jing Piao ),( Ho Jin You ),( Byoung Sam Yoo ),( Young Taek Yang ),( Jin Won Hyun ) 한국생화학분자생물학회 (구 한국생화학회) 2006 생화학분자생물학회 춘계학술발표논문집 Vol.2006 No.-

Triphlorethol-a improves the non-homologous end joining and base-excision repair capacity impaired by formaldehyde.

Zhang, Rui,Kang, Kyoung Ah,Piao, Mei Jing,Kim, Ki Cheon,Lee, Nam Ho,You, Ho Jin,Hyun, Jin Won Taylor Francis 2011 Journal of toxicology and environmental health. Pa Vol.74 No.12

<P>Formaldehyde (HCHO) generates reactive oxygen species (ROS) that induce DNA base modifications and DNA strand breaks and contributes to mutagenesis and other pathological processes. DNA non-homologous end-joining (NHEJ), a major mechanism for repairing DNA double-stranded breaks (DSB) in mammalian cells, involves the formation of a Ku protein heterodimer and recruitment of a DNA-dependent protein kinase catalytic subunit (DNA-PKcs) to the site of DNA damage. HCHO treatment induced DSB and decreased the protein expressions of Ku 70 and phosphorylated DNA-PKcs. Triphlorethol-A reduced DNA strand breaks and restored the expression of NHEJ-related proteins. In response to oxidative DNA base damage, 8-oxoguanine DNA glycosylase 1 (OGG1) plays a vital role in repair of 8-hydroxy-2'-deoxyguanosine (8-OhdG) via the base-excision repair (BER) process. In this study, HCHO significantly increased 8-OhdG levels, whereas triphlorethol-A lowered 8-OhdG levels. Suppression of 8-OhdG formation by triphlorethol-A was related to enhanced OGG1 protein expression. Triphlorethol-A also enhanced the expression of phosphorylated Akt (the active form of Akt), a regulator of OGG1, which was found to be decreased by HCHO treatment. The phosphoinositol 3-kinase (PI3K)-specific inhibitor LY294002 abolished the cytoprotective effects induced by triphlorethol-A, suggesting that OGG1 restoration by triphlorethol-A is involved in the PI3K/Akt pathway. These results suggest that triphlorethol-A may protect cells against HCHO-induced DNA damage via enhancement of NHEJ and BER capacity.</P>

Preventive Effect of 7,8-Dihydroxyflavone against Oxidative Stress Induced Genotoxicity

Zhang, Rui,Kang, Kyoung Ah,Piao, Mei Jing,Ko, Dong Ok,Wang, Zhi Hong,Chang, Weon Young,You, Ho Jin,Lee, In Kyung,Kim, Bum Joon,Kang, Sam Sik,Hyun, Jin Won Pharmaceutical Society of Japan 2009 Biological & pharmaceutical bulletin Vol.32 No.2

<P>We elucidated the protective effect of 7,8-dihydroxyflavone against hydrogen peroxide (H<SUB>2</SUB>O<SUB>2</SUB>)-induced DNA damage. We found that 7,8-dihydroxyflavone scavenges 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and intracellular reactive oxygen species (ROS). 7,8-Dihydroxyflavone with antioxidant effect prevented the H<SUB>2</SUB>O<SUB>2</SUB>-induced cellular DNA damage, as evidenced by comet tail, 8-hydroxy-2′-deoxyguanosine (8-OHdG) content, and phospho-histone H2A.X protein expression. Hence, 7,8-dihydroxyflavone was shown to protect cell <I>via</I> the inhibition of apoptosis induced by H<SUB>2</SUB>O<SUB>2</SUB>. This was substantiated by decreased apoptotic nuclear fragmentation, decreased sub-G<SUB>1</SUB> cell population, and decreased DNA fragmentation. Furthermore, 7,8-dihydroxyflavone activated the protein kinase B (PKB, Akt) signal pathway, which is a major survival signal pathway. In addition, LY294002, which is phosphatidylinositol 3 kinase (PI3K, upstream of Akt) inhibitor, attenuated the protective effect of 7,8-dihydroxyflavone against H<SUB>2</SUB>O<SUB>2</SUB>-induced cell damage. In conclusion, 7,8-dihydroxyflavone was shown to possess cytoprotective properties against oxidative stress by scavenging intracellular ROS and enhancing Akt activity.</P>

Adaptive polymorphism of tetrameric alpha-amylase inhibitors in wild emmer wheat

Ji-Rui Wang,Mei Deng,Ya-Xi Liu,Xin Qiao,Zhen-Hong Chen,Qian-Tao Jiang,Zhi-En Pu,Yu-Ming Wei,Eviatar Nevo,You-Liang Zheng 한국유전학회 2011 Genes & Genomics Vol.33 No.4

α-Amylase inhibitors are attractive candidates for the control of seed weevils as these insects are highly dependent on starch as an energy source. Wheat tetrameric α-amylase inhibitor (WTAI) is a mixture (60 kDa) of 3 units: WTAI-CM2 plus 2 WTAI-CM3 plus WTAI-CM16, where none of the subunits is active on its own. A total of 334 gene sequences were obtained from 14 populations (131 accessions= genotypes) of wild emmer wheat. The frequencies of SNPs in WTAI-CM2,WTAI-CM3 and WTAI-CM16 were 1 out of 87.6, 101.4, and 108.0 bases, where 5, 5 and 4 SNPs were detected in the coding sequence, respectively. The nucleotide sequence of each unit of tetrameric α-amylase inhibitors were much more conserved than that of dimeric or monomeric inhibitors. The wild emmer wheat populations showed diversity on three WTAI loci,both between and within populations. It was revealed that WTAI were naturally selected for across populations by a ratio of dN/dS as expected. The results of purifying and positive selection hypothesis (p<0.05) also showed that the sequences of WTAI were contributed by natural selection, which ensures the protein function conservation as well as the inhibition diversity with insects amylase enzyme. Ecological factors, singly or in combination, explained a significant proportion of the variations in the SNPs. Ecological factors have an important evolutionary role in gene differentiation at these loci, and tetrameric α-amylase inhibitors are obviously adaptively selected under different environments.

Effect of Zanthoxylum alkylamides on glucose metabolism in streptozotocin‑induced diabetic Sprague–Dawley rats

Wang Rui,You Yu-ming,Liu Xiong 한국응용생명화학회 2021 Applied Biological Chemistry (Appl Biol Chem) Vol.64 No.1

This research aimed at investigating the hypoglycemic effect of Zanthoxylum alkylamides and whether TRPV1 receptor could participate in the glucose metabolism by using streptozotocin-induced diabetic rat model. The results showed that the blood glucose measured in the Zanthoxylum alkylamides treated group (ALK) showed significantly lower values than that in the model group (Model). Significant improvements in the oral glucose tolerance as well as plasma insulin and hepatic glycogen were also observed in the ALK group, when compared to the model group. However, the improving effects of Zanthoxylum alkylamides on glucose metabolism disorder in diabetic rats were markedly inhibited by capsazepine as the TRPV1 receptor antagonist. In addition, there were significant differences in the levels of mRNA and protein of phosphoenolpyruvate carboxylase (PEPCK), gucose-6-phosphatase (G6Pase), glucokinase (GK) and cannabinoid receptor l (CB1) in the livers of the ALK group compared to model group. Meanwhile, ALK group also exhibited a remarkable increase in the pancreatic-duodenal homeobox 1 (PDX-1), glucose transporter 2 (GLUT 2), GK levels and a significant decrease in the expression levels of CB1 in the pancreas, while the presence of capsazepine would affected the expression of these genes. These findings indicate that Zanthoxylum alkylamides could ameliorate the glucose metabolism disorder in diabetic rats. Furthermore, the TRPV1 receptor could participate in regulating the expressions of genes and proteins related to glucose metabolism and insulin secretion in the liver and pancreas, and takes a role in the hypoglycemic process of Zanthoxylum alkylamides.

Atrial secretion of ANP is suppressed in renovascular hypertension: shifting of ANP secretion from atria to the left ventricle

Tan, Rui,Ahn, You Mee,Kim, Hye Yoom,Lee, Yun Jung,Cho, Kyung Woo,Kang, Dae Gill,Lee, Ho Sub American Physiological Society 2018 American journal of physiology, Heart and circulat Vol.315 No.3

<P> In the present study, the change in secretion of atrial natriuretic peptide (ANP) from the atria was defined in hypertension accompanied by ventricular hypertrophy and increased synthesis of ANP. To identify the change of the secretion and mechanisms involved, experiments were performed in isolated perfused beating atria from sham-operated normotensive and renovascular hypertensive rats. Expression of ANP, natriuretic peptide receptor (NPR)-C, components of the renin-angiotensin system, and muscarinic signaling pathway was measured in cardiac tissues. Basal levels of ANP secretion and acetylcholine (ACh)- and stretch-induced activation of ANP secretion were suppressed in the atria from hypertensive compared with normotensive rats. ACh increased ANP secretion via M2 muscarinic ACh receptor-ACh-sensitive K<SUP>+</SUP> channel signaling. In hypertensive rats, ANP concentration increased in the left ventricle but decreased in the right ventricle. The atrial concentration of ANP was not changed in hypertensive compared with normotensive rats. ANP mRNA expression was accentuated in the left ventricle but suppressed in the other cardiac chambers in the hearts of hypertensive rats. NPR-C expression was inversely related to ANP mRNA levels. Angiotensin II type 1 receptor (AT1R) expression was accentuated in the cardiac chambers from hypertensive rats compared with normotensive rats, whereas angiotensin II type 2 receptor, M2 muscarinic receptor, and Kir3.4 channels were suppressed. AT1R blockade with losartan reversed the change observed in hypertensive rats. The present findings indicate that renovascular hypertension shifts the major site of ANP secretion and synthesis from the atria to the left ventricle through modulation of the expression of ANP, NPR-C, AT1R, and the M2 muscarinic signaling pathway. </P><P> NEW & NOTEWORTHY Renovascular hypertension suppresses the atrial secretion of ANP and shifts the major site of the regulation of ANP secretion and synthesis from atria to the hypertrophied left ventricle possibly via modulation of the expression of ANP, natriuretic peptide receptor-C, angiotensin II subtype 1 receptor, and M2 muscarinic signaling pathway. </P>

Prospective comparison of hybrid capture 2 and SPF10-LiPA for carcinogenic human papillomavirus detection and risk prediction of cervical cancer: a population-based cohort study in China

Li Dong,Rui-Mei Feng,Li Zhang,Xiao-qian Xu,Xue-Lian Zhao,Margaret Zhuoer Wang,You-Lin Qiao,Fang-Hui Zhao 대한부인종양학회 2017 Journal of Gynecologic Oncology Vol.28 No.5

Objective: To investigate the extent of the cross-reactivity of hybrid capture 2 (HC2) assay andevaluate the potential effect of cross-reactivity on the long-term risk for cervical cancer andprecancers. Methods: Based on the Shanxi Province Cervical Cancer Screening Study-I (SPOCCS-I)cohort from 2005 to 2014 in Shanxi, China, SPF10-line probe assay (LiPA) was performedin all 598 HC2 positive and 300 random-selected HC2 negative cervical specimens. Tenyearcumulative incidence rate (CIR) of cervical intraepithelial neoplasia grade 2 or worse(CIN2+) of these two tests was evaluated using Kaplan-Meier methods. Possible humanpapillomavirus (HPV) types to be cross-reacted by HC2 were also analyzed. Results: The overall agreement between HC2 and SPF10-LiPA for detecting carcinogenic HPVwas 73.27%. The highest 10-year cumulative risk of CIN2+ was observed in both HC2 positiveand LiPA-carcinogenic HPV positive women (25.70%; 95% confidence interval [CI]=23.55%–27.91%), followed by HC2 positive but LiPA-non-carcinogenic HPV positive women (9.97%;95% CI=8.57%–11.50%), HC2 negative but LiPA-carcinogenic HPV positive (2.56%; 95%CI=2.44%–2.70%) and HC2 positive but LiPA-HPV negative (1.85%; 95% CI=1.78%–1.92%)women. The proportion of cross-reactivity of HC2 with untargeted carcinogenic types was8.9%, most of which were attributable to HPV26, 73, 82, 69, 71, 53, 11, 43, and 54. Conclusion: The noticeable high risk of CIN2+ in women infected with cross-reacted noncarcinogenicHPV and low risk in those with miss-to-detective carcinogenic HPV supportedan overall good clinical performance of HC2 for a general cervical cancer screening.