Investigation on reverse flow characteristics in U-tubes under two-phase natural circulation

Chu, Xi,Li, Mingrui,Chen, Wenzhen,Hao, Jianli Korean Nuclear Society 2020 Nuclear Engineering and Technology Vol.52 No.5

The vertically inverted U-tube steam generator (UTSG) is widely used in the pressurized water reactor (PWR). The reverse flow behavior generally exists in some U-tubes of a steam generator (SG) under both single- and two-phase natural circulations (NCs). The behavior increases the flow resistance in the primary loop and reduces the heat transfer in the SG. As a consequence, the NC ability as well as the inherent safety of nuclear reactors is faced with severe challenges. The theoretical models for calculating single- and two-phase flow pressure drops in U-tubes are developed and validated in this paper. The two-phase reverse flow characteristics in two types of SGs are investigated base on the theoretical models, and the effects of the U-tube height, bending radius, inlet steam quality and primary side pressure on the behavior are analyzed. The conclusions may provide some promising references for SG optimization to reduce the disadvantageous behavior. It is also of significance to improve the NC ability and ensure the PWR safety during some accidents.

HPLC Determination of Malondialdehyde in ECV304 Cell Culture Medium for Measuring the Antioxidant Effect of Vitexin-4"-O-glucoside

Xi-xiang Ying,Hai-bo Li,Zheng-yun Chu,Yan-jun Zhai,Ai-jing Leng,Xun Liu,Wen-jie Zhang,Ting-guo Kang,Chun Xin 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.7

To investigate the antioxidant effect of vitexin-4"-O-glucoside, a flavone glycoside, isolated from the leaves of Crataegus pinnatifida Bge. var. major, we developed a simple and sensitive high-performance liquid chromatography (HPLC) method to determine levels of malondialdehyde (MDA) in ECV304 cell culture medium after induction by tert-butyl-hydroperoxide (TBHP). The preparation of analyzed samples involved a one-step derivatization with thiobarbituric acid (TBA). HPLC analysis was performed on a SynergiTM Hydro-RP, a polar end-capped C18 column (250×4.6 mm, 4 μm), using an acetonitrile-ammonium acetate aqueous solution (10 mM, pH 6.8) as the mobile phase under linear gradient conditions with UV detection at 532 nm. The calibration curve was linear over 0.0125-1.25 μM MDA (r = 0.9951). Relative standard deviations (RSDs) of intra-day and inter-day precision were less than 6.1% and 5.0%, respectively. The mean recovery was 96.9 ± 1.6%. The lower limit of quantification (LLOQ) of MDA was 0.0125 μM. This chromatographic method was successfully applied to investigating the in vitro antioxidant effect of vitexin-4"-O-glucoside. Vitexin-4"-O-glucoside (120 M) protected ECV304 cells from peroxidation induced by TBHP.

Fertility and prognosis assessment between bleomycin/etoposide/cisplatin and paclitaxel/carboplatin chemotherapy regimens in the conservative treatment of malignant ovarian germ cell tumors: a multicenter and retrospective study

Ran Chu,Penglin Liu,Jingying Chen,Xiaodong Cheng,Kezhen Li,Yanci Che,Jianliu Wang,Li Li,Xi Zhang,Shu Yao,Li Song,Ying Zhao,Changzhen Huang,Ying Xue,Xiyu Pan,Junting Li,Zhongshao Chen,Jie Jiang,Beihua 대한부인종양학회 2023 Journal of Gynecologic Oncology Vol.34 No.2

Objective: To evaluate the impact of bleomycin/etoposide/cisplatin (BEP) and paclitaxel/carboplatin (PC) chemotherapy regimens on the fertility and prognostic outcomes in malignant ovarian germ cell tumor (MOGCT) patients who underwent fertility-sparing surgery (FSS). Methods: A propensity score matching algorithm was performed between the BEP and PC groups. The χ2 test and the Kaplan-Meier method were used to compare the fertility outcome, disease-free survival (DFS) and overall survival (OS). The Cox proportional hazards regression analysis was used to identify risk factor of DFS. Results: We included 213 patients, 185 (86.9%) underwent BEP chemotherapy, and 28 (13.1%) underwent PC chemotherapy. The median age was 22 years (range, 8–44 years), and the median follow-up period was 63 months (range, 2–191 months). Fifty-one (29.3%) patients had a pregnancy plan, and 35 (85.4%) delivered successfully. In the before and after propensity score matching cohorts, there were no significant differences in spontaneous abortion, selective termination of pregnancy, during-pregnancy status, and live birth between the BEP and PC groups (p>0.05). Fourteen (6.6%) patients experienced recurrence, including 11 (5.9%) in the BEP group and 3 (10.7%) in the PC group. Four (1.9%) patients in the BEP group died. Kaplan-Meier analysis revealed no significant differences in DFS (p=0.328) and OS (p=0.446) between the BEP and PC groups, and the same survival results were observed in the after matching cohort. Conclusion: The PC regimen is as safe as the BEP regimen for MOGCT patients with fertility preservation treatment, and no differences were observed in fertility and clinical prognosis.

HPLC Determination of Malondialdehyde in ECV304 Cell Culture Medium for Measuring the Antioxidant Effect of Vitexin-4"-O-glucoside

Ying, Xi-Xiang,Li, Hai-Bo,Chu, Zheng-Yun,Zhai, Yan-Jun,Leng, Ai-Jing,Liu, Xun,Xin, Chun,Zhang, Wen-Jie,Kang, Ting-Guo 대한약학회 2008 Archives of Pharmacal Research Vol.31 No.7

To investigate the antioxidant effect of vitexin-4"-O-glucoside, a flavone glycoside, isolated from the leaves of Crataegus pinnatifida Bge. var. major, we developed a simple and sensitive high-performance liquid chromatography (HPLC) method to determine levels of malondialdehyde (MDA) in ECV304 cell culture medium after induction by tert-butyl-hydroperoxide (TBHP). The preparation of analyzed samples involved a one-step derivatization with thiobarbituric acid (TBA). HPLC analysis was performed on a $Synergi^{TM}$ Hydro-RP, a polar end-capped $C_{18}$ column ($250{\times}4.6\;mm$, $4\;{\mu}m$), using an acetonitrile-ammonium acetate aqueous solution (10 mM, pH 6.8) as the mobile phase under linear gradient conditions with UV detection at 532 nm. The calibration curve was linear over $0.0125-1.25\;{\mu}M$ MDA (r=0.9951). Relative standard deviations (RSDs) of intra-day and inter-day precision were less than 6.1% and 5.0%, respectively. The mean recovery was $96.9\;{\pm}\;1.6%$. The lower limit of quantification (LLOQ) of MDA was $0.0125\;{\mu}M$. This chromatographic method was successfully applied to investigating the in vitro antioxidant effect of vitexin-4"-O-glucoside. Vitexin-4"-O-glucoside (120 M) protected ECV304 cells from peroxidation induced by TBHP.

삼차신경초중 1예

이기찬,최종구,전동휘,주정화 대한신경외과학회 1977 Journal of Korean neurosurgical society Vol.6 No.1

Trigeminal neurinomas are relatively rare tumors that arise from the sheath of Schwann and. constitute 2.9% of intracranial neurinomas and 0.26% of all brain tumors. The most cases are confined to the middle fossa and arising from the Gasserian ganglion. In slight fewer cases the tumors occupy the cerebellopontine angle. In minority it is an hourglass form both situations. By reason of their rarity, the complex clinical problems which may present and the difficult technical aspects involved in their removal, neurinomas of the Gasserian ganglion are of extreme interest. We are reporting a case of trigeminal neurinoma which was arised from the right Gasserian ganglion and located in both situations of middle and posterior cranial fossas. A 37 year-old female was admitted to our department with characteristic symptoms and signs involving many cranial nerves, cerebellum and cerebral peduncle. We chose temporal craniotomy and approached to and exposed the mass by extradural and intradural techniques. Complete removal of the tumor occupying the middle and posterior cranial fossas are accomplished satisfactorily.

A collaborative client participant fusion system for realistic remote conferences

Song, W.,Wen, M.,Xi, Y.,Chu, P. M.,Vu, H.,Kayumiy, S. J.,Cho, K. Springer Science + Business Media 2016 The Journal of supercomputing Vol.72 No.7

<P>Remote conferencing systems provide a shared environment where people in different locations can communicate and collaborate in real time. Currently, remote video conferencing systems present separate video images of the individual participants. To achieve a more realistic conference experience, we enhance video conferencing by integrating the remote images into a shared virtual environment. This paper proposes a collaborative client participant fusion system using a real-time foreground segmentation method. In each client system, the foreground pixels are extracted from the participant images using a feedback background modeling method. Because the segmentation results often contain noise and holes caused by adverse environmental lighting conditions and substandard camera resolution, a Markov Random Field model is applied in the morphological operations of dilation and erosion. This foreground segmentation refining process is implemented using graphics processing unit programming, to facilitate real-time image processing. Subsequently, segmented foreground pixels are transmitted to a server, which fuses the remote images of the participants into a shared virtual environment. The fused conference scene is represented by a realistic holographic projection.</P>

투명 스크린 기반 인터랙티브 상품 전시 시스템

박지선 ( Jisun Park ),치옥용 ( Yuong Xi ),푸옹 ( Phuong Chu ),김준오 ( Junoh Kim ),조경은 ( Kyungeun Cho ) 한국정보처리학회 2017 한국정보처리학회 학술대회논문집 Vol.24 No.1

최근 투명 스크린을 이용한 인터랙티브 상품 전시 시스템은 다양하게 상용화되고 있다. 하지만 기존 시스템은 사용자와 실제 상품간의 인터랙션이 아닌 사용자와 투명 스크린 속 콘텐츠간의 인터랙션에 불과하다. 본 논문에서는 동작인식 기술 및 실시간 사용자 분석을 통한 선호상품 추천기술을 결합한 투명 스크린 기반 인터랙티브 상품 전시 시스템을 구현 및 실험하였다.

AcuD Gene Knockout Attenuates the Virulence of Talaromyces marneffei in a Zebrafish Model

( Jiao Feng ),( Zhiwen Chen ),( Liya He ),( Xing Xiao ),( Chunmei Chen ),( Jieming Chu ),( Eleftherios Mylonakis ),( Liyan Xi ) 한국균학회 2019 Mycobiology Vol.47 No.2

Talaromyces marneffei is the only dimorphic species in its genus and causes a fatal systemic mycosis named talaromycosis. Our previous study indicated that knockdown of AcuD gene (encodes isocitrate lyase of glyoxylate bypass) of T. marneffei by RNA interference approach attenuated the virulence of T. marneffei, while the virulence of the AcuD knockout strains was not studied. In this study, T. marneffei-zebrafish infection model was successfully established through hindbrain microinjection with different amounts of T. marneffei yeast cells. After co-incubated at 28_C, the increasing T. marneffei inoculum doses result in greater larval mortality; and hyphae generation might be one virulence factor involved in T. marneffeizebrafish infection. Moreover, the results demonstrated that the virulence of the DAcuD was significantly attenuated in this Zebrafish infection model.

Magnesium isoglycyrrhizinate inhibits L-type Ca2+ channels, Ca2+ transients, and contractility but not hERG K+ channels

Yue Lin,Yuanyuan Zhang,Qiongtao Song,Tao Song,Xue Han,Ying Zhang,Xuan Zhang,Xi Chu,Fenghua Zhang,Li Chu,Jianping Zhang 대한약학회 2017 Archives of Pharmacal Research Vol.40 No.10

To explore the cardiovascular protective effectsof Magnesium isoglycyrrhizinate (MI), especially theunderlying cellular mechanisms related to L-type calciumchannels and myocardial contractility, and to examine theeffects of MI on hERG K? current expressed in HEK293cells. We used the whole-cell patch clamp technique,video-based edge detection and dual excitation fluorescencephotomultiplier systems to explore the effect of MIon L-type Ca2? currents (ICa-L) and cell contraction in ratcardiomyocytes. We also examined the rapidly activatingdelayed rectifier potassium current (IKr) expressed inHEK293 cells using a perforated patch clamp. MI inhibitedICa-L in a dose-dependent manner, with a half-maximalinhibitory concentration (IC50) of 0.22 mg/ml, and themaximal inhibitory effect was 61.10 ± 0.59%. MI at aconcentration of 0.3 mg/ml reduced cell shortening by24.12 ± 3.97% and the peak value of the Ca2? transient by36.54 ± 4.96%. MI had no significant influence on hERGK? channels expressed in HEK293 cells at all testpotentials. MI exerts protective effects on the heart via theinhibition of ICa-L and cell shortening in rat cardiomyocytes. However, MI had no significant influence on IKr;thus, MI may exert cardioprotective effects without causingdrug-induced long QT syndrome.

Novel and Effective Almagate Enema for Hemorrhagic Chronic Radiation Proctitis and Risk Factors for Fistula Development

Yuan, Zi-Xu,Ma, Teng-Hui,Zhong, Qing-Hua,Wang, Huai-Ming,Yu, Xi-Hu,Qin, Qi-Yuan,Chu, Li-Li,Wang, Lei,Wang, Jian-Ping Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.2

Radiation proctitis is a common complication after radiotherapy for pelvic malignant tumors. This study was conducted to assess the efficacy of novel almagate enemas in hemorrhagic chronic radiation proctitis (CRP) and evaluate risk factors related to rectal deep ulcer or fistula secondary to CRP. All patients underwent a colonoscopy to confirm the diagnosis of CRP and symptoms were graded. Typical endoscopic and pathological images, risk factors, and quality of life were also recorded. A total of 59 patients were enrolled. Gynecological cancers composed 93.1% of the primary malignancies. Complete or obvious reduction of bleeding was observed in 90% (53/59) patients after almagate enema. The mean score of bleeding improved from 2.17 to 0.83 (P<0.001) after the enemas. The mean response time was 12 days. No adverse effects were found. Moreover, long-term successful rate in controlling bleeding was 69% and the quality of life was dramatically improved (P=0.001). The efficacy was equivalent to rectal sucralfate, but the almagate with its antacid properties acted more rapidly than sucralfate. Furthermore, we firstly found that moderate to severe anemia was the risk factor of CRP patients who developed rectal deep ulcer or fistulas (P= 0.015). We also found abnormal hyaline-like thick wall vessels, which revealed endarteritis obliterans and the fibrosis underlying this disease. These findings indicate that almagate enema is a novel effective, rapid and well-tolerated method for hemorrhagic CRP. Moderate to severe anemia is a risk factor for deep ulceration or fistula.