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Zhang AL, Peng SX, Ren HT, Zhang T, Zhang JF, Xu Y, Guo ZY, Chen JE. Study on space charge compensation in negative hydrogen ion beam. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02B915. [PMID: 26932087 DOI: 10.1063/1.4932557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Negative hydrogen ion beam can be compensated by the trapping of ions into the beam potential. When the beam propagates through a neutral gas, these ions arise due to gas ionization by the beam ions. However, the high neutral gas pressure may cause serious negative hydrogen ion beam loss, while low neutral gas pressure may lead to ion-ion instability and decompensation. To better understand the space charge compensation processes within a negative hydrogen beam, experimental study and numerical simulation were carried out at Peking University (PKU). The simulation code for negative hydrogen ion beam is improved from a 2D particle-in-cell-Monte Carlo collision code which has been successfully applied to H(+) beam compensated with Ar gas. Impacts among ions, electrons, and neutral gases in negative hydrogen beam compensation processes are carefully treated. The results of the beam simulations were compared with current and emittance measurements of an H(-) beam from a 2.45 GHz microwave driven H(-) ion source in PKU. Compensation gas was injected directly into the beam transport region to modify the space charge compensation degree. The experimental results were in good agreement with the simulation results.
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Ren QQ, Fu SJ, Zhao Q, Guo ZY, Ji F, Chen MG, Wu LW, He XS. Prognostic value of preoperative peripheral monocyte count in patients with hepatocellular carcinoma after liver transplantation. Tumour Biol 2016; 37:8973-8. [PMID: 26753965 DOI: 10.1007/s13277-015-4758-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 12/29/2015] [Indexed: 12/12/2022] Open
Abstract
Prognostic value of peripheral monocyte, as a member of inflammatory cells, was widely being investigated. The aim of this study was to evaluate the prognostic value of preoperative peripheral blood monocyte count for hepatocellular carcinoma (HCC) patients who underwent liver transplantation (LT) and the relationship between monocyte count and tumor-related characteristics. We retrospectively analyzed the clinical data of 101 HCC patients after LT. Preoperative monocyte count and demographic, clinical, and pathologic data were analyzed. The optimal cutoff value of monocyte count was 456/mm(3), with the sensitivity and specificity of 69.4 and 61.5 %, respectively. Elevated preoperative peripheral blood monocyte count was significantly associated with large tumor size. The 1-, 3-, and 5-year disease-free survival (DFS) (80.9, 70.1, and 53.3 % vs 55.1, 38.7, and 38.7 %, P = 0.007) and overall survival (OS) rates (95.7, 76.6, and 64.8 % vs 72.2, 44.1, and 36.1 %, P = 0.002) of HCC patients in the peripheral blood monocyte count ≤456/mm(3) group were higher than those in the peripheral blood monocyte count >456/mm(3) group. In conclusion, elevated preoperative peripheral blood monocyte count was significantly associated with advanced tumor stage and it can be considered as a prognostic factor for HCC patients after LT.
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Zhu L, Dong D, Hua X, Guo Z, Liang D. Ammonia nitrogen removal from acetylene purification wastewater from a PVC plant by struvite precipitation. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2016; 74:508-515. [PMID: 27438257 DOI: 10.2166/wst.2016.239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Acetylene purification wastewater (APW) usually contains high concentrations of ammonia nitrogen (NH4-N), which is generated during the production of acetylene in a polyvinylchloride manufacturing plant. In this study, a struvite precipitation method was selected to remove NH4-N from the APW. Laboratory-scale batch experiments were performed to investigate the effects of the initial APW pH, phosphate (PO4(3-)) concentration, magnesium (Mg(2+)) concentration, and sources of PO4(3-) and Mg(2+) on NH4-N removal. The results indicated that the initial APW pH had a significant effect on the removal of NH4-N, while the other factors had relatively minor effect. The NH4-N could be effectively removed at an optimum initial APW pH of 9.5, when Na2HPO4·12H2O and MgSO4·7H2O were both applied to NH4-N at a ratio of 1.2. Under these conditions, the efficiency of removal of NH4-N, total nitrogen and chemical oxygen demand were 85%, 84% and 18%, respectively. The X-ray diffraction analysis indicated that the precipitates were dominated by struvite. The scanning electron microscopy analysis of the precipitates showed a typical morphology of stick-like and prismatic crystals with coarse surface. The energy dispersive spectroscopy analysis indicated that the precipitates contained P, O, Mg and Ca.
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Zhang SL, Wu YC, Cheng F, Guo ZY, Chen JF. Anti-PRRSV effect and mechanism of tetrahydroaltersolanol C in vitro. JOURNAL OF ASIAN NATURAL PRODUCTS RESEARCH 2015; 18:303-314. [PMID: 26488075 DOI: 10.1080/10286020.2015.1072516] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Porcine reproductive and respiratory syndrome virus (PRRSV) is an important arterivirus that causes substantial economic losses to the swine industry. Current control strategies against PRRSV are still inadequate and there is an urgent need for new antiviral therapies. Tetrahydroaltersolanol C (TD-C) is a new anthraquinone derivative isolated from the marine-derived fungi. In the present study, we first demonstrated its anti-PRRSV activity in vitro through assessing the inhibition of TD-C on cytopathic effect, viral ORF7 gene and N protein expressions, progeny virions production by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, relative-quantitative RT-PCR, Western blotting, and indirect immunofluorescence assay. Our experimental results showed that TD-C could significantly inhibit PRRSV replication in a dose-dependent manner. The 50% effective concentration, 50% cytotoxic concentration and the selectivity index were 12.11, 395.31 μM, and 32.64, respectively. Furthermore, the possible anti-PRRSV mechanism was explored by virucidal assay, virus adsorption inhibition assay, and the time-of-addition assay. The results showed that TD-C might inhibit the internalization and replication of PRRSV, but did not directly inactivate the virus or block its adsorption to cell surface. In conclusion, our findings indicated that TD-C possessed a significant anti-PRRSV activity, and provided a strong basis for further exploration of this compound as an antiviral agent against PRRSV.
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Luo D, Chen LL, Guo ZY, Tu X, Deng ZS. Solanapyrone Analogues from the Endophytic Fungus Nigrospora sp. Chem Nat Compd 2015. [DOI: 10.1007/s10600-015-1459-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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81
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Guo ZY, Yao GD, Fu LP, Fu ZG, Hou B. Effect of recombinant human endostatin on the expression of c-Myc and bFGF in mouse gastric cancer cells. GENETICS AND MOLECULAR RESEARCH 2015; 14:5258-65. [PMID: 26125720 DOI: 10.4238/2015.may.18.17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The aim of this study was to observe the effects of re-combinant human endostatin on the proliferation and apoptosis of mouse gastric cancer cells, and explore some possible mechanisms of recom-binant human endostatin inhibition of cancer. A murine gastric cancer xenograft model was established. A total of 20 mice were divided into two groups (control and experimental groups). The expression of c-Myc and basic fibroblast growth factor (bFGF) was determined by reverse transcription-polymerase chain reaction, Western blotting, and immu-nohistochemical staining methods. Tumor volume was measured and a growth curve was calculated. The tumor diameter in the experimental group was significantly smaller than that in the control group after treat-ment with endostatin for 21 days. The expression levels of c-Myc and bFGF in the experimental group were significantly lower than those of the control group (P < 0.05). There was a positive correlation between the expression of c-Myc and bFGF in the experimental group. Microvessel density was significantly inhibited in the experimental group (P < 0.05). These results demonstrated that recombinant human endostatin could in-hibit tumor metastasis by inhibition of the expression of c-Myc and bFGF in gastric cancer tissue as well as by inhibition of angiogenesis.
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Liu CX, Wang L, Chen JF, Guo ZY, Tu X, Deng ZS, Zou K. Paraconfuranones A-H, eight new furanone analogs from the insect-associated fungus Paraconiothyrium brasiliense MZ-1. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:317-322. [PMID: 25594922 DOI: 10.1002/mrc.4197] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2014] [Revised: 11/11/2014] [Accepted: 11/13/2014] [Indexed: 06/04/2023]
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83
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Wang H, Wu W, Wei D, Guo Z, Wang S. Hollow fiber supported ionic liquid membrane microextraction for preconcentration of kanamycin sulfate with electrochemiluminescence detection. J Electroanal Chem (Lausanne) 2014. [DOI: 10.1016/j.jelechem.2014.10.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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84
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Ye H, Wang DP, Zhang CZ, Zhang LJ, Wang HC, Li ZH, Chen Z, Zhang T, Cai CJ, Ju WQ, Ma Y, Guo ZY, He XS. Pathological characteristics of liver allografts from donation after brain death followed by cardiac death in pigs. ACTA ACUST UNITED AC 2014; 34:687-691. [PMID: 25318878 DOI: 10.1007/s11596-014-1337-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2014] [Revised: 08/25/2014] [Indexed: 01/08/2023]
Abstract
Donation after brain death followed by circulatory death (DBCD) is a unique practice in China. The aim of this study was to define the pathologic characteristics of DBCD liver allografts in a porcine model. Fifteen male pigs (25-30 kg) were allocated randomly into donation after brain death (DBD), donation after circulatory death (DCD) and DBCD groups. Brain death was induced by augmenting intracranial pressure. Circulatory death was induced by withdrawal of life support in DBCD group and by venous injection of 40 mL 10% potassium chloride in DCD group. The donor livers were perfused in situ and kept in cold storage for 4 h. Liver tissue and common bile duct samples were collected for hematoxylin and eosin staining, TUNEL testing and electron microscopic examination. Spot necrosis was found in hepatic parenchyma of DBD and DBCD groups, while a large area of necrosis was shown in DCD group. The apoptosis rate of hepatocytes in DBD [(0.56±0.30)%] and DBCD [(0.50 ± 0.11)%] groups was much lower than that in DCD group [(3.78±0.33)%] (P<0.05). And there was no significant difference between DBD group and DBCD group (P>0.05)). The structures of bile duct were intact in both DBD and DBCD groups, while the biliary epithelium was totally damaged in DCD group. Under electron microscope, the DBD hepatocytes were characterized by intact cell membrane, well-organized endoplasmic reticulum, mild mitochondria edema and abundant glycogens. Broken cell membrane, mild inflammatory cell infiltration and sinusoidal epithelium edema, as well as reduced glycogen volume, were found in the DBCD hepatocytes. The DCD hepatocytes had more profound cell organelle injury and much less glycogen storage. In conclusion, the preservation injury of DBCD liver allografts is much less severe than that of un-controlled DCD, but more severe than that of DBD liver allografts under electron microscope, which might reflect post-transplant liver function to some extent.
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85
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Lv YK, Zhang JQ, Guo ZY, Zhang W, Sun HW. Determination of Tetracyclines Residues in Egg, Milk, and Milk Powder by Online Coupling of A Precolumn Packed with Molecular Imprinted Hybrid Composite Materials to RP-HPLC-UV. J LIQ CHROMATOGR R T 2014. [DOI: 10.1080/10826076.2013.873873] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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86
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Guo ZY, Li P, Huang W, Wang JJ, Liu YJ, Liu B, Wang YL, Wu SB, Kennelly EJ, Long CL. Antioxidant and anti-inflammatory caffeoyl phenylpropanoid and secoiridoid glycosides from Jasminum nervosum stems, a Chinese folk medicine. PHYTOCHEMISTRY 2014; 106:124-133. [PMID: 25107663 DOI: 10.1016/j.phytochem.2014.07.011] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2013] [Revised: 01/18/2014] [Accepted: 01/20/2014] [Indexed: 06/03/2023]
Abstract
Eight compounds including four caffeoyl phenylpropanoid glycosides, jasnervosides A-D (1-4), one monoterpenoid glycoside, jasnervoside E (5), and three secoiridoid glycosides, jasnervosides F-H (10-12), were isolated from the stems of Jasminum nervosum Lour. (Oleaceae), along with four known compounds, poliumoside (6), verbascoside (7), α-l-rhamnopyranosyl-(1→3)-O-(α-l-rhamnopyranosyl(1→6)-1-O-E-caffeoyl-β-d-glucopyranoside (8), and jaspolyanthoside (9). Their structures were elucidated on the basis of their physicochemical and spectroscopic properties. Compounds 1, 2, 4 and 11 displayed potent antioxidant activities in the DPPH assay, while 2 and 3 displayed good activities against LPS-induced TNF-α and IL-1β production in BV2 cells. Compounds 1-5 and 10-12 were evaluated for their cytotoxic activities against three human cancer cell lines (A-549, Bel-7402, and HCT-8), but none displayed significant activity.
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87
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Zhu MF, Ye XP, Huang YY, Guo ZY, Zhuang ZF, Liu SH. Detection of methemoglobin in whole blood based on confocal micro-Raman spectroscopy and multivariate statistical techniques. SCANNING 2014; 36:471-478. [PMID: 24729434 DOI: 10.1002/sca.21143] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Accepted: 03/04/2014] [Indexed: 06/03/2023]
Abstract
Raman spectroscopy has been shown to have the potential for revealing oxygenated and spin ability of hemoglobin. In this study, confocal micro-Raman spectroscopy is developed to monitor the effect of sodium nitrite on oxyhemoglobin (HbO2 ) in whole blood. We observe that the band at 1,638 cm(-1) which is sensitive to the oxidation state decreases dramatically, while the 1,586 cm(-1) (low-spin state band) reduces both in methemoglobin (MetHb) and poisoning blood. Our results show that adding in sodium nitrite lead to the transition from HbO2 (Fe(2+) ) to MetHb (Fe(3+) ) in whole blood, and the iron atom converts from the low spin state to the high spin state with a delocalization from porphyrin plane. Moreover, multivariate statistical techniques, including principal components analysis (PCA) and linear discriminant analysis (LDA) are employed to develop effective diagnostic algorithms for classification of spectra between pure blood and poisoning blood. The diagnostic algorithms based on PCA-LDA yield a diagnostic sensitivity of 100% and specificity of 100% for separating poisoning blood from normal blood. Receiver operating characteristic (ROC) curve further confirms the effectiveness of the diagnostic algorithm based on PCA-LDA technique. The results from this study demonstrate that Raman spectroscopy combined with PCA-LDA algorithms has tremendous potential for the non-invasive detection of nitrite poisoning blood.
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88
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Dong R, Guo ZY, Ding JR, Zhou YY, Wu H. Gastrointestinal symptoms: A comparison between patients undergoing peritoneal dialysis and hemodialysis. World J Gastroenterol 2014; 20:11370-11375. [PMID: 25170224 PMCID: PMC4145778 DOI: 10.3748/wjg.v20.i32.11370] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 04/28/2014] [Accepted: 07/11/2014] [Indexed: 02/06/2023] Open
Abstract
AIM: To compare the prevalence and diversity of gastrointestinal (GI) symptoms in patients undergoing peritoneal dialysis (PD) and hemodialysis (HD).
METHODS: Two hundred and ninety-four end-stage renal disease patients participated in the study, including 182 HD and 112 PD patients. Dimension scores were calculated from a modified gastrointestinal symptom rating scale (GSRS) 18-item questionnaire, including items concerning eating dysfunction, and were used for measuring GI symptoms. Information on patient age, condition contributing to end-stage renal disease and the most recent dialysis adequacy assessment (serum Kt/V urea value) was obtained from the follow-up database and by interviewing patients and/or reviewing the medical records. Differences between the HD and PD groups were evaluated using Student’s t, Pearson’s χ2 or Fisher’s exact tests.
RESULTS: The overall prevalence of GI symptoms, defined by a GSRS > 1, in end-stage renal disease patients was 70.7% (208/294), which differed between HD and PD patients (76.4% vs 61.6%, P < 0.01). HD patients had a higher prevalence of constipation, abdominal pain and diarrhea compared to PD patients (36.3% vs 17.9%, 32.4% vs 5.4%, 17.6% vs 4.5%, respectively, P < 0.05). PD patients had a higher prevalence of reflux compared to HD patients (32.1% vs 24.2%, P < 0.05). Additionally, reflux and eating dysfunction were more severe in PD patients (GSRS: 1.71 ± 1.15 vs 1.30 ± 0.67, 1.57 ± 0.84 vs 1.39 ± 0.61, respectively, P < 0.05), whereas HD patients had greater abdominal pain, diarrhea and constipation (GSRS: 1.22 ± 0.39 vs 1.04 ± 0.19, 1.19 ± 0.53 vs 1.07 ± 0.35, 1.51 ± 0.83 vs 1.23 ± 0.58, respectively, P < 0.05). Finally, 14.8% (27/182) of HD patients presented with more than three GI symptoms, compared to 7.2% (8/112) of PD patients (P < 0.01).
CONCLUSION: HD and PD patients differ in prevalence, severity and diversity of GI symptoms.
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Han M, Guo ZY, Zhao Q, Wang XP, Yuan XP, Jiao XY, Yang CH, Wang DP, Ju WQ, Wu LW, Hu AB, Tai Q, Ma Y, Zhu XF, He XS. Liver transplantation using organs from deceased organ donors: a single organ transplant center experience. Hepatobiliary Pancreat Dis Int 2014; 13:409-15. [PMID: 25100126 DOI: 10.1016/s1499-3872(14)60274-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
BACKGROUND In 2011, a pilot program for deceased organ donation was initiated in China. We describe the first successful series of liver transplants in the pilot program. METHODS From July 2011 to August 2012, our center performed 26 liver transplants from a pool of 29 deceased donors. All organ donation and allograft procurement were conducted according to the national protocol. The clinical data of donors and recipients were collected and summarized retrospectively. RESULTS Among the 29 donors, 24 were China Category II donors (organ donation after cardiac death), and five were China Category III donors (organ donation after brain death followed by cardiac death). The recipients were mainly the patients with hepatocellular carcinoma. The one-year patient survival rate was 80.8% with a median follow-up of 422 (2-696) days. Among the five mortalities during the follow-up, three died of tumor recurrence. In terms of post-transplant complications, 9 recipients (34.6%) experienced early allograft dysfunction, 1 (3.8%) had non-anastomotic biliary stricture, and 1 (3.8%) was complicated with hepatic arterial thrombosis. None of these complications resulted in patient death. Notably, primary non-function was not observed in any of the grafts. CONCLUSION With careful donor selection, liver transplant from deceased donors can be performed safely and plays a critical role in overcoming the extreme organ shortage in China.
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Wang S, Wang S, Guo Z. Electrochemiluminescence Sensor for Selective Preconcentration and Sensitive Detection of Napropamide Using Water-Soluble Sulfonated Graphene. ELECTROANAL 2014. [DOI: 10.1002/elan.201300629] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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91
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Ren HT, Zhao J, Peng SX, Lu PN, Zhou QF, Xu Y, Chen J, Zhang T, Zhang AL, Guo ZY, Chen JE. Handling radiation generated during an ion source commissioning. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A930. [PMID: 24593509 DOI: 10.1063/1.4833925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Radiation is an important issue, which should be carefully treated during the design and commissioning of an ion source. Measurements show that X-rays are generated around the ceramics column of an extraction system when the source is powered up to 30 kV. The X-ray dose increases greatly when a beam is extracted. Inserting the ceramic column into a metal vacuum box is a good way to block X-ray emission for those cases. Moreover, this makes the online test of an intense H(+) ion beam with energy up to 100 keV possible. However, for deuteron ion source commissioning, neutron and gamma-ray radiation become a serious topic. In this paper, we will describe the design of the extraction system and the radiation doses of neutrons and gamma-rays measured at different D(+) beam energy during our 2.45 GHz deuteron electron cyclotron resonance ion source commissioning for PKUNIFTY (PeKing University Neutron Imaging FaciliTY) project at Peking University.
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Ren HT, Peng SX, Lu PN, Zhao J, Zhou QF, Song ZZ, Yuan ZX, Yu JX, Guo ZY, Chen JE. Commissioning and operation of the deuteron injector for PKUNIFTY project. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A706. [PMID: 24593440 DOI: 10.1063/1.4826337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
PKUNIFTY (PeKing University Neutron Imaging FaciliTY), a thermal neutron imaging facility based on a 2 MeV RFQ accelerator, has been constructed at Peking University. Its deuteron injector, which consists of a 2.45 GHz permanent magnet electron cyclotron resonance (PMECR) deuteron ion source and a two-solenoid low energy beam transport (LEBT), aims at producing and delivering 50 mA, 50 keV deuteron beam with a duty factor of 10% (1 ms, 100 Hz). In the preliminary tests of RFQ accelerator, the ECR ion source and LEBT are required to operate at various duty factors (from 1% to 10%). The deuteron ion source has been tested with different pulse widths for this reason. In order to optimize the transmission parameters, the beam current at the exit of RFQ as a function of solenoids tuning and steering magnets tuning are carefully studied. The beam emittance at the entrance of RFQ has been measured with space charge compensation by different argon gas (RG) pressure from 1.6 × 10(-4) Pa to 4.7 × 10(-3) Pa. The measuring results show the best compensating pressure is 3.5 × 10(-3) Pa with a minimal normalized rms emittance of 0.12 pi mm mrad. During the commissioning, we found the purity of deuteron gas is an important factor which severely affects ECR discharge and plasma intensity inside the ion source chamber. The detailed experimental results obtained during the commissioning are discussed in this paper.
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Ren HT, Peng SX, Xu Y, Zhao J, Lu PN, Chen J, Zhang AL, Zhang T, Guo ZY, Chen JE. Plasma studies of the permanent magnet electron cyclotron resonance ion source at Peking University. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A927. [PMID: 24593506 DOI: 10.1063/1.4832065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
At Peking University (PKU) we have developed several 2.45 GHz Permanent Magnet Electron Cyclotron Resonance ion sources for PKUNIFTY, SFRFQ, Coupled RFQ&SFRFQ, and Dielectric-Wall Accelerator (DWA) projects (respectively, 50 mA of D(+), 10 mA of O(+), 10 mA of He(+), and 50 mA of H(+)). In order to improve performance of these ion sources, it is necessary to better understand the principal factors that influence the plasma density and the atomic ion fraction. Theoretical analysis about microwave transmission and cut-off inside the discharge chamber were carried out to study the influence of the discharge chamber diameters. As a consequence, experimental studies on plasma density and ion fraction with different discharge chamber sizes have been carried out. Due to the difficulties in measuring plasma density inside the discharge chamber, the output beam current was measured to reflect the plasma density. Experimental results show that the plasma density increases to the maximum and then decreases significantly as the diameter changed from 64 mm to 30 mm, and the atomic ion fraction has the same tendency. The maximum beam intensity was obtained with the diameter of 35 mm, but the maximum atomic ion fraction with a diameter of 40 mm. The experimental results are basically accordant with the theoretical calculation. Details are presented in this paper.
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Lv YK, Zhang JQ, Guo ZY, Wang WC, Li BH. Molecularly Imprinted Solid-Phase Extraction of Tetracyclines Residue from Milk Using Internal-Surface Reversed-Phase Hybrid Composite Packing Materials. ACTA ACUST UNITED AC 2014. [DOI: 10.14233/ajchem.2014.16198] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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95
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Bu HB, Wang F, Lin HY, Guo ZY, Yuan SX, Pan LL, Xu XJ, Li XR, Wang GL, Lin RC. [Nondestructive recognization of mountain cultivated ginseng and garden cultivated ginseng by FTIR microspectroscopy]. GUANG PU XUE YU GUANG PU FEN XI = GUANG PU 2013; 33:3028-3031. [PMID: 24555374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Fourier transform infrared (FTIR) microspectroscopy technology is the combination of the FTIR spectrometer and the microscope. This technology is of simple preparation of the samples, can be used in micro-area analysis and micro-samples, and reflect the nature of the samples spectra. Panax ginseng include mountain cultivated ginseng (MCG), garden cultivated ginseng (GCG) and mountain wild ginseng (MWG), but the excavation of MWG is prohibited in China. So, only MCG and GCG were collected and recorded in Chinese pharmacopoeia. In this study, we developed a discriminant analysis (DA) method for recognition of MCG and GCG using FTIR microspectroscopy technology. Twenty MCG samples and twenty four GCG samples were obtained, and their spectra of IR microspectroscopy were collected. Then 33 samples were randomly selected into calibration set and the remaining 11 of the samples were selected into validation set. The authors optimized the pretreatment method, the principal components, the modeling region and the scanning parts when developing the models. The optimized model of discriminant analysis was developed using the pretreatment multiplicative scatter correction (MSC) + Savitzky-Golay filter (SG) smoothing, the region 3 932.14-669.18 cm(-1), 4 principal components and the rhizome part. The accuracy of the optimized model got up to 100%. The result demonstrated that infrared microspectroscopy technology combined with DA is of simple operation, rapid, nondestructive and effective, and can be applied to recognize MCG and GCG.
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Xiong HL, Guo ZY, Li SX, Li N, Liu SH, Ji YH. In vivo detection of Hirschsprung's disease by optical coherence tomography in rats. Phys Med Biol 2013; 58:1549-61. [PMID: 23417024 DOI: 10.1088/0031-9155/58/5/1549] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Hirschsprung's disease (HSCR) is a developmental intestinal obstruction, which is often diagnosed with a repeated biopsy. Optical coherence tomography (OCT) is a noninvasive, real-time imaging modality. This study aims to investigate the feasibility of diagnosis of HSCR, the targeted biopsies of suspicious tissues and the location of operative treatment using OCT. An HSCR Sprague-Dawley (SD) rat model (benzalkonium chloride-treated (BAC-treated)) was used. Colon tissues with BAC-treated and without BAC-treated were imaged using OCT. To establish OCT criteria for identification of HSCR, OCT images were compared with corresponding histology images and muscle layer thickness was measured. Furthermore, attenuation coefficients of OCT signals were calculated to illustrate the differences between tissues with BAC-treated and without BAC-treated. Our results show that OCT images of colon tissues with HSCR are well correlated with histology images. In comparison with a muscle layer without HSCR, the thickness of muscle layer with HSCR is increased significantly. The muscle layer in colon tissues with HSCR for 6 weeks had a higher attenuation coefficient than those without HSCR. However, the attenuation coefficient of those with HSCR for 3 weeks had no obvious change. In conclusion, the study demonstrates for the first time that OCT has the potential for diagnosis, biopsy and location of HSCR in vivo.
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Zhuang ZF, Zhu MF, Guo ZY, Liu SH. Second harmonic generation in 3-d uniform arrangement of type I collagen on nonlinear optics microscopy. SCANNING 2013; 35:12-16. [PMID: 23417663 DOI: 10.1002/sca.21029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 04/15/2012] [Indexed: 06/01/2023]
Abstract
Second harmonic microscopic imaging and spectroscopy technology has become a powerful tool for biomedical studies, especially in fibrosis-related diseases research. And type I collagen is the major risk factors for fibrotic diseases. In this study, model for three-dimensional (3-D) uniform arrangement type I collagen is set up for researching the second harmonic generation (SHG) on nonlinear optics microscopy. Based on this model, we discuss the influence of different length and size collagen in 3-D arrangement type I collagen. Results can guide us to neatly judge the size, length, and molecules density effect on SHG. For practical application, this theoretical approach can lead us to analyze different severity of collagen diseases.
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98
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Sun LL, Shao CL, Hang H, Guo ZY, Xing Q, Wang CY. New polyhydroxylated steroid from the South China Sea gorgonian Anthogorgia caerulea. Nat Prod Res 2012; 27:1159-66. [PMID: 22946558 DOI: 10.1080/14786419.2012.717287] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
One new polyhydroxylated steroid, caerulsteroid A (1), along with nine known analogues (2-10), was isolated from the gorgonian coral Anthogorgia caerulea collected from the South China Sea. The structure of the new compound was elucidated by 1-D and 2-D NMR, and mass spectrometry. The absolute configuration of 1 was assigned on the basis of the absolute configurations of the related congeners 2 and 3, which were determined by application of the modified Mosher's method. The isolated compounds were assayed for their cytotoxicity, antimicrobial activity and lethality towards brine shrimp Artemia salina.
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99
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Yang KL, Wei MY, Shao CL, Fu XM, Guo ZY, Xu RF, Zheng CJ, She ZG, Lin YC, Wang CY. Antibacterial anthraquinone derivatives from a sea anemone-derived fungus Nigrospora sp. JOURNAL OF NATURAL PRODUCTS 2012; 75:935-941. [PMID: 22545792 DOI: 10.1021/np300103w] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Chemical investigation of a marine-derived fungus Nigrospora sp., isolated from an unidentified sea anemone, yielded two new hydroanthraquinone analogues, 4a-epi-9α-methoxydihydrodeoxybostrycin (1) and 10-deoxybostrycin (2), together with seven known anthraquinone derivatives (3-9). The structures of the two new compounds were established through extensive NMR spectroscopy as well as a single-crystal X-ray diffraction analysis using Cu Kα radiation. The antibacterial activities of compounds 1-9 and 10 acetyl derivatives (6a, 7a, 8a-8g, 9a) were evaluated in vitro. Compound 6a, the acetylated derivative of 6, exhibited promising activity against Bacillus cereus with an MIC value of 48.8 nM, which was stronger than that of the positive control ciprofloxacin (MIC = 1250 nM). Analysis of the antibacterial screening data for the metabolites and their acetyl derivatives revealed the key structural features required for this activity.
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100
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Li N, Li SX, Guo ZY, Zhuang ZF, Li R, Xiong K, Chen SJ, Liu SH. Micro-Raman spectroscopy study of the effect of Mid-Ultraviolet radiation on erythrocyte membrane. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2012; 112:37-42. [PMID: 22561009 DOI: 10.1016/j.jphotobiol.2012.04.005] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2012] [Revised: 03/30/2012] [Accepted: 04/04/2012] [Indexed: 12/14/2022]
Abstract
Mid-Ultraviolet (UVB) has a significant influence on human health. In this study, human erythrocytes were exposed to UVB to investigate the effects of UVB radiation on erythrocytes membrane. And Micro-Raman spectroscopy was employed to detect the damage. Principal component analysis (PCA) was used to classify the control erythrocytes and the irradiated erythrocytes. Results showed that the erythrocytes membrane was damaged by Mid-Ultraviolet (UVB) radiation. The intensity of the Raman peaks at 1126 cm(-1) and 1082 cm(-1) were used to calculate the Longitudinal Order-Parameters in Chains (S(trans)) which can present the liquidity and ionic permeability of erythrocyte membrane. After UVB radiation for 30 min, both the liquidity and ionic permeability decreased. At the same time, the intensity of the peaks at 1302 cm(-1) (α-helix), 1254 cm(-1) (random coil), 1452 cm(-1) and 1430 cm(-1) (CH(2)/CH(3) stretch) have also changed which indicated the membrane protein also been damaged by UVB. In the whole process of radiation, the more UVB radiation dose the more damage on the erythrocyte membrane.
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