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Yang Z, Xing X, Xiao J, Lu J, Weng J, Jia W, Ji L, Shan Z, Liu J, Tian H, Ji Q, Zhu D, Ge J, Lin L, Chen L, Guo X, Zhao Z, Li Q, Zhou Z, Shan G, Yang W. Prevalence of cardiovascular disease and risk factors in the Chinese population with impaired glucose regulation: the 2007-2008 China national diabetes and metabolic disorders study. Exp Clin Endocrinol Diabetes 2013; 121:372-4. [PMID: 23616189 DOI: 10.1055/s-0033-1341520] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Cardiovascular disease (CVD) is one of the most common chronic diseases in China. This aim of this study is to determine the prevalence of CVDs and risk factors in Chinese impaired glucose regulation subjects.We used a multistage, stratified sampling method to select subjects from the general Chinese population aged 20 years and older. Subjects underwent an oral glucose tolerance test to identify normal glucose tolerance (NGT) and impaired glucose regulation including isolated impaired fasting glucose (i-IFG), impaired glucose tolerance (i-IGT), and combined IFG/IGT and diabetic mellitus (DM). A logistic regression analysis was performed to examine the association between glucose abnormalities and CVD events.We identified that 34 293 subjects had NGT, 1 469 i-IFG, 4 571 i-IGT, 957 IFG/IGT and 4 949 DM. The age-sex standardized prevalence rate of cardiovascular disease was 1.06% (95% CI 0.87-1.28), 1.79% (95% CI 1.37-2.33) and 3.83% (95% CI 2.79-5.24) in NGT, impaired glucose regulation and DM, respectively. Among impaired glucose subjects, prevalence of defined CVD risk factors (smoking, overweight, obesity, hypertension and dyslipidemia) was 29.52% (95% CI: 27.8-31.21), 36.25% (95% CI: 34.29-38.26), 10.05% (95% CI: 8.86-11.37), 36.43% (95% CI: 34.53-38.36) and 69.96% (95% CI: 67.87-71.98), respectively. Compared to 1 risk factor, the odds ratios (ORs) of CVDs with 2, 3 or 4 risk factors were 1.94 (95% CI: 0.74-5.09), 2.76 (95% CI: 1.06-7.21) and 5.84 (95% CI: 1.68-20.26), respectively. Additionally, compared to i-IFGs, ORs of CVDs with i-IGT and IFG/IGT were 2.88 (95%CI 1.36-6.01) and 2.12 (95% CI 0.83-5.44), respectively.The prevalence of cardiovascular risk factors was high in the Chinese impaired glucose regulation population. The postprandial hyperglycemia is more associated with CVD than isolated fasting hyperglycemia.
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Zhu S, Zhang H, Dong Y, Xu Z, Chen D, Wang L, Gan Y, Wang F, Wang Y, Xing X, Hu S, Li Z, Long L, Liu L, Zhong Y. The correlation between T helper type 17 cells and clinical characters in Chinese paediatric patients with chronic hepatitis B. Clin Exp Immunol 2013; 171:307-12. [PMID: 23379437 DOI: 10.1111/cei.12028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2012] [Indexed: 12/15/2022] Open
Abstract
Interleukin (IL)-17-mediated immune response has been shown to play a critical role in inflammation-associated disease. However, its role in the pathogenesis of chronic hepatitis B virus (HBV) in paediatric patients remains unknown. We investigated the frequency of T helper type 17 (Th17) cells and evaluated the association between the Th17 and clinical characters in paediatric patients with chronic hepatitis B (CHB). The frequency of Th17 cells was detected by flow cytometry analyses from 65 paediatric patients with CHB and nine healthy controls. The degree of hepatic inflammation was graded using the histological activity index (HAI). Compared with healthy controls, the frequency of Th17 cells in peripheral blood was significantly higher in paediatric patients with CHB. The proportion of Th17 cells was higher in the patients with higher HAI score (G2-G3) compared to those subjects with lower HAI score (G0-G1), but the frequency of Th17 cells had no correlation with serum HBV DNA loads or alanine aminotransferase levels. Compared with the younger age group (age 1-6 years), Th17 cell frequency was higher in the older age group (age 7-18 years). Peripheral Th17 cell frequency is associated closely with inflammation activity of liver tissues in paediatric patients with CHB.
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Li S, Liu M, Lou J, Xing X, Wu J, Hu Y, Cai X, Xu F, Sun NX, Duh JG. Microwave frequency performance and high magnetic anisotropy of nanocrystalline Fe70Co30-B films prepared by composition gradient sputtering. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2013; 13:1091-1094. [PMID: 23646578 DOI: 10.1166/jnn.2013.5973] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
The fabrication and high-frequency ferromagnetic performances of nanocrystalline Fe70Co30-B soft magnetic films were investigated. It is revealed that the composition gradient sputtering method dramatically improves the high-frequency soft magnetic properties of the as-prepared films. This method gives rise to almost a linearly-increased distribution of compositions and residual stress. As a result, a very high ferromagnetic resonance frequency up to 6.7 GHz, high uniaxial magnetic anisotropic field up to 450 Oe, and low magnetic loss were obtained in as-deposited samples, which are particularly in favor of the integration between magnetic films and microwave components.
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Li S, Liu M, Lou J, Xing X, Qiu J, Lin J, Cai Z, Xu F, Sun NX, Duh JG. Tunable microwave frequency performance of nanocomposite Co2MnSi/PZN-PT magnetoelectric coupling structure. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2013; 13:1182-1185. [PMID: 23646598 DOI: 10.1166/jnn.2013.6050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Nanocrystalline Co2MnSi Heusler alloy films were deposited on the PZN-PT substrates by a composition gradient sputtering method. It is revealed that this multiferroic heterostructure shows very strong magnetoelectric coupling, leading to continuously tunable microwave frequency characteristics by electric field. With the increase of electric field intensity from 0 to 6 kV/cm, the magnetic anisotropy field H(K) increases from 90 Oe to 182 Oe with an increment of 102%, corresponding to a ME coefficient of 15.3 Oe cm/kV; the ferromagnetic resonance frequency f(FMR) shifts from 3.38 to 4.82 GHz with an increment of deltaf(FMR) = 1440 MHz or deltaf(FMR)/f(FMR) = 43%; moreover, the damping constant alpha dramatically decreases from 0.035 to 0.018. These merits demonstrate that this nanocomposite multiferroic structure is promising in fabrication of tunable microwave components.
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Li Y, Li X, Li D, Lu J, Xing X, Yan F, Li Y, Wang X, Iezzi R, De Cobelli F. Multicenter, intraindividual comparison of single-dose gadobenate dimeglumine and double-dose gadopentetate dimeglumine for MR angiography of the supra-aortic arteries (the Supra-Aortic VALUE study). AJNR Am J Neuroradiol 2012; 34:847-54. [PMID: 23042922 DOI: 10.3174/ajnr.a3298] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Gadobenate dimeglumine has markedly higher R1 relaxivity compared to gadopentetate dimeglumine meaning that lower doses can be used to achieve similar contrast enhancement. Our aim was to prospectively compare single-dose gadobenate dimeglumine with double-dose gadopentetate dimeglumine for contrast-enhanced MRA of the supra-aortic vasculature. MATERIALS AND METHODS Forty-six patients (37 men, 9 women; mean age, 63.5±10.1 years) with known or suspected steno-occlusive disease of the supra-aortic vessels underwent 2 identical CE-MRA examinations at 1.5T. Contrast agents were administered in randomized order, with the 2-fold greater volume of gadopentetate dimeglumine injected at a 2 times faster rate. Image assessment was performed by 3 independent blinded readers for vessel anatomic delineation, detection/exclusion of pathology, and global preference. Diagnostic performance (sensitivity, specificity, accuracy, PPV, and NPV) for detection of ≥60% stenosis was determined for 39/46 patients who underwent preinterventional DSA. Data were analyzed by using the Wilcoxon signed-rank, McNemar, and Wald tests in terms of the noninferiority of single-dose gadobenate dimeglumine compared with double-dose gadopentetate dimeglumine. Quantitative enhancement (signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR)) was also compared. RESULTS All images were technically adequate. No differences (P=1.0) were noted by any reader for any qualitative parameter. All readers considered single-dose gadobenate dimeglumine and double-dose gadopentetate dimeglumine equivalent in at least 42/46 patients (91.3% three-reader agreement) for all parameters. Nonsignificant superiority for gadobenate dimeglumine was reported for all diagnostic performance indicators (sensitivity: 82.7%-88.5% versus 75.0%-80.8%; specificity: 96.4%-98.6% versus 94.6%-98.6%; accuracy: 94.6%-96.1% versus 92.4%-94.9%; PPV: 81.5%-91.5% versus 73.7%-90.7%; NPV: 96.8%-97.8% versus 95.4%-96.4%). No differences (P>.05) in quantitative enhancement were noted. CONCLUSIONS The image quality and diagnostic performance achieved with 0.1-mmol/kg gadobenate dimeglumine is at least equivalent to that achieved with 0.2-mmol/kg gadopentetate dimeglumine.
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Pan C, Xing X, Han P, Zheng S, Ma J, Liu J, Lv X, Lu J, Bader G. Efficacy and tolerability of vildagliptin as add-on therapy to metformin in Chinese patients with type 2 diabetes mellitus. Diabetes Obes Metab 2012; 14:737-44. [PMID: 22369287 DOI: 10.1111/j.1463-1326.2012.01593.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
AIM To investigate the efficacy and tolerability of vildagliptin as add-on therapy to metformin in Chinese patients with type 2 diabetes mellitus (T2DM) inadequately controlled with metformin. METHODS This was a 24-week, randomized, double-blind, placebo-controlled study. Patients with T2DM (N = 438) with haemoglobin A1c (HbA1c) of 7.0-10.0% and fasting plasma glucose (FPG) <15 mmol/l (<270 mg/dl) were randomized (1 : 1 : 1) to vildagliptin 50 mg bid, vildagliptin 50 mg qd or placebo in addition to metformin. RESULTS The treatment groups were well balanced at baseline [mean HbA1c, 8.0%, FPG, 8.8 mmol/l (158 mg/dl); body mass index, 25.5 kg/m(2) ]. The adjusted mean change (AMΔ) in HbA1c at endpoint was -1.05 ± 0.08%, -0.92 ± 0.08% and -0.54 ± 0.08% in patients receiving vildagliptin 50 mg bid, 50 mg qd and placebo, respectively. The between-treatment difference (vildagliptin 50 mg bid-placebo) was -0.51 ± 0.11%, p < 0.001. A greater proportion of vildagliptin-treated patients met at least one responder criterion (82.1 and 70.7%) compared to placebo-treated patients (60.4%). The AMΔ at endpoint for FPG with vildagliptin 50 mg bid, -0.95 mmol/l (-17.1 mg/dl); 50 mg qd, -0.84 mmol/l (-15.1 mg/dl) was significantly different compared with the placebo -0.26 mmol/l (-4.68 mg/dl) (p ≤ 0.001). Adverse events (AEs) were reported as 34.2, 36.5 and 37.5% for patients receiving vildagliptin 50 mg bid, 50 mg qd or placebo, respectively. Two patients in the vildagliptin 50 mg qd and one in the placebo group reported serious AEs, which were not considered to be related to the study drug; one incidence of hypoglycaemic event was reported in the vildagliptin 50 mg bid group. CONCLUSION Vildagliptin as add-on therapy to metformin improved glycaemic control and was well tolerated in Chinese patients who were inadequately controlled by metformin only.
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Green MP, Richter M, Xing X, Scherson D, Hanson KJ, Ross PN, Carr R, Lindau I. In-situ STM studies of electrochemical underpotential deposition of Pb on Au(111). J Microsc 2011. [DOI: 10.1111/j.1365-2818.1988.tb01455.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Xu F, Wang J, Chen S, Qin W, Yu Z, Zhao H, Xing X, Li H. Strain improvement for enhanced production of cellulase in Trichoderma viride. APPL BIOCHEM MICRO+ 2011. [DOI: 10.1134/s0003683811010212] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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109
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Xu F, Wang J, Chen S, Qin W, Yu Z, Zhao H, Xing X, Li H. Strain improvement for enhanced production of cellulase in Trichoderma viride. PRIKLADNAIA BIOKHIMIIA I MIKROBIOLOGIIA 2011; 47:61-65. [PMID: 21438472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The filamentous fungi Trichoderma species produce extracellular cellulase. The current study was carried out to obtain an industrial strain with hyperproduction of cellulase. The wild-type strain, Trichoderma viride TL-124, was subjected to successive mutagenic treatments with UV irradiation, low-energy ion beam implantation, atmospheric pressure non-equilibrium discharge plasma (APNEDP), and N-methyl-N'-nitro-N-nitrosoguanidine to generate about 3000 mutants. Among these mutants, T. viride N879 strain exhibited the greatest relevant activity: 2.38-fold filter paper activity and 2.61-fold carboxymethyl cellulase, 2.18-fold beta-glucosidase, and 2.27-fold cellobiohydrolase activities, compared with the respective wild-type activities, under solid-state fermentation using the inexpensive raw material wheat straw as a substrate. This work represents the first application of APNEDP in eukaryotic microorganisms.
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Liu J, Chen M, Yang X, Fang S, Xing X, Huang H, Zhou L. Identification of novel interaction proteins of set in trichloroethylene-treated L-02 liver cells. Toxicol Lett 2010. [DOI: 10.1016/j.toxlet.2010.03.274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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111
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Xing X, Rui Q, Wang D. Lethality toxicities induced by metal exposure during development in nematode Caenorhabditis elegans. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 83:530-536. [PMID: 19588066 DOI: 10.1007/s00128-009-9816-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2009] [Accepted: 06/25/2009] [Indexed: 05/28/2023]
Abstract
Lethality changes were investigated during development in 4 h metal exposed Caenorhabditis elegans. Exposure to examined metals caused severe lethality toxicities in L1- and L2-larvae, in L3-larvae exposed to examined metals at concentrations of 50 and 100 microM and to Pb, Hg, and Cr at the concentration of 2.5 microM, in L4-larvae exposed to examined metals at concentrations of 50 and 100 microM, and in adults exposed to Pb, Hg, and Cr at the concentration of 100 microM. Moreover, the lethality toxicities induced by Pb and Hg in L1 larvae for 4 h could be largely comparable to those in young adults for 24 h.
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Xue CY, Li L, Guo LL, Li JH, Zhang ML, Xing X. The axial frontonasal flap for reconstruction of large nasal-tip defects based on modified nasal subunits in East Asians. Clin Exp Dermatol 2009; 34:426-8. [PMID: 19309377 DOI: 10.1111/j.1365-2230.2008.03103.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
The nasal tip is a prominent landmark on the face, and skin carcinomas of this area are very common. Moderate and large deep skin defects of the nasal tip normally represent a difficult reconstructive challenge. Nasal-tip reconstruction techniques have evolved to allow not only filling of the gap, but cosmetic and functional retention. Numerous flap options are available to reconstruct the defect of the tip of the nose. In this paper, we report the technique of the axial frontonasal flap and its use in reconstruction of large nasal-tip defects in East Asians. The axial frontonasal flap described is a good alternative for reconstruction of nasal-tip defects > 15 mm in diameter, with excellent aesthetic results. This technique is reliable, yields excellent functional and cosmetic results, and we believe that it is a valuable alternative to other techniques of reconstruction for defects of the nasal tip.
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Wolfgramm F, Xing X, Cerè A, Predojević A, Steinberg AM, Mitchell MW. Bright filter-free source of indistinguishable photon pairs. OPTICS EXPRESS 2008; 16:18145-18151. [PMID: 18958092 DOI: 10.1364/oe.16.018145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We demonstrate a high-brightness source of pairs of indistinguishable photons based on a type-II phase-matched doubly-resonant optical parametric oscillator operated far below threshold. The cavityenhanced down-conversion output of a PPKTP crystal is coupled into two single-mode fibers with a mode coupling efficiency of 58%. The high degree of indistinguishability between the photons of a pair is demonstrated by a Hong-Ou-Mandel interference visibility of higher than 90% without any filtering at an instantaneous coincidence rate of 450,000 pairs/s per mW of pump power per nm of down-conversion bandwidth. For the degenerate spectral mode with a linewidth of 7 MHz at 795 nm a rate of 70 pairs/(s mW MHz) is estimated, increasing the spectral brightness for indistinguishable photons by two orders of magnitude compared to similar previous sources.
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Hou Y, Woo HK, Wang P, Xing X, Ng CY, Lau KC. Vacuum ultraviolet pulsed field ionization-photoelectron and infrared-photoinduced Rydberg ionization study of trans-1,3-butadiene. J Chem Phys 2008; 129:114305. [DOI: 10.1063/1.2973635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Xing X, Wang P, Reed B, Baek SJ, Ng CY. Infrared Vacuum-Ultraviolet Laser Pulsed Field Ionization-Photoelectron Study of CH3Br+(X̃2E3/2). J Phys Chem A 2008; 112:9277-82. [DOI: 10.1021/jp8019649] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Xing X, Wang P, Woo HK, Bahng MK, Baek SJ, Ng C. Rotationally resolved infrared–vacuum ultraviolet–pulsed field ionization–photoelectron depletion method for infrared spectroscopic studies of neutral molecules. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2008.02.073] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lau KC, Woo HK, Wang P, Xing X, Ng CY. Vacuum ultraviolet laser pulsed field ionization-photoelectron study ofcis-dichloroethene. J Chem Phys 2006; 124:224311. [PMID: 16784278 DOI: 10.1063/1.2207610] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The vacuum ultraviolet (VUV) laser pulsed field ionization photoelectron (PFI-PE) spectrum of cis-dichloroethene (cis-ClCH[Double Bond]CHCl) has been measured in the energy region of 77 600-79 500 cm(-1). On the basis of the semiempirical simulation of the origin PFI-PE band, we have obtained the IE(cis-ClCH[Double Bond]CHCl) to be 77 899.5+/-2.0 cm(-1) (9.658 39+/-0.000 25 eV). The assignment of the vibrational bands resolved in the VUV-PFI-PE spectrum are guided by high-level ab initio calculations of the vibrational frequencies for cis-ClCH[Double Bond]CHCl(+) and the Franck-Condon factors for the ionization transitions. Combining the results of the present VUV-PFI-PE measurement and the recent VUV-infrared-photoinduced Rydberg ionization study, the vibrational frequencies for eleven of the twelve vibrational modes of cis-ClCH[Double Bond]CHCl(+) have been experimentally determined: nu(1) (+)(a(1))=181 cm(-1), nu(2) (+)(a(2))=277 cm(-1), nu(3) (+)(b(2))=580 cm(-1), nu(4) (+)(b(1))=730 cm(-1), nu(5) (+)(a(1))=810 cm(-1), nu(6) (+)(a(2))=901 cm(-1), nu(8) (+)(a(1))=1196 cm(-1), nu(9) (+)(b(2))=1348 cm(-1), nu(10) (+)(a(1))=1429 cm(-1), nu(11) (+)(b(2))=3067 cm(-1), and nu(12) (+)(a(1))=3090 cm(-1)). These values are compared to theoretical anharmonic vibrational frequencies obtained at the MP2/6-311G(2df,p) and CCSD(T)/6-311G(2df,p) levels. The IE prediction for cis-ClCH[Double Bond]CHCl has also been calculated with the wave function based CCSD(T)/CBS method, which involves the approximation to the complete basis set (CBS) and the high-level correlation corrections. The theoretical IE(cis-ClCH[Double Bond]CHCl)=9.668 eV thus obtained is found to have a deviation of less than 10 meV with respect to the experimental IE value.
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Wang P, Woo HK, Lau KC, Xing X, Ng CY, Zyubin AS, Mebel AM. Infrared vibrational spectroscopy of cis-dichloroethene in Rydberg states. J Chem Phys 2006; 124:64310. [PMID: 16483210 DOI: 10.1063/1.2166851] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We have measured the infrared (IR) vibrational spectrum for cis-dichloroethene (cis-ClCH[Double Bond]CHCl) in excited Rydberg states with the effective principal quantum numbers n(*)=9, 13, 17, 21, 28, and 55 using the vacuum ultraviolet-IR-photoinduced Rydberg ionization (VUV-IR-PIRI) scheme. Although the IR frequencies observed for the vibrational bands nu(11) (*) (asymmetric C-H stretch) and nu(12) (*) (symmetric C-H stretch) are essentially unchanged for different n(*) states, suggesting that the IR absorption predominantly involves the ion core and that the Rydberg electron behaves as a spectator; the intensity ratio for the nu(11) (*) and nu(12) (*) bands [R(nu(11) (*)nu(12) (*))] is found to decrease smoothly as n(*) is increased. This trend is consistent with the results of a model ab initio quantum calculation of R(nu(11) (*)nu(12) (*)) for excited cis-ClCH[Double Bond]CHCl in n(*)=3-18 states and the MP26-311++G(2df,p) calculations of R(nu(11)nu(12)) and R(nu(11) (+)nu(12) (+)), where R(nu(11)nu(12))[R(nu(11) (+)nu(12) (+))] represents the intensity ratio of the nu(11)(nu(11) (+)) asymmetric C-H stretching to the nu(12)(nu(12) (+)) symmetric C-H stretching vibrational bands for cis-ClCH[Double Bond]CHCl (cis-ClCH[Double Bond]CHCl(+)). We have also measured the IR-VUV-photoion (IR-VUV-PI) and IR-VUV-pulsed field ionization-photoelectron depletion (IR-VUV-PFI-PED) spectra for cis-ClCH[Double Bond]CHCl. These spectra are consistent with ab initio calculations, indicating that the IR absorption cross section for the nu(12) band is negligibly small compared to that for the nu(11) band. While the VUV-IR-PIRI measurements have allowed the determination of nu(11) (+)=3067+/-2 cm(-1), nu(12) (+)=3090+/-2 cm(-1), and R(nu(11) (+)nu(12) (+)) approximately 1.3 for cis-ClCH=CHCl(+), the IR-VUV-PI and IR-VUV-PFI-PED measurements have provided the value nu(11)=3088.5+/-0.2 cm(-1) for cis-ClCH=CHCl.
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Wang P, Xing X, Lau KC, Woo HK, Ng CY. Rovibrational-state-selected pulsed field ionization-photoelectron study of methyl iodide using two-color infrared-vacuum ultraviolet lasers. J Chem Phys 2004; 121:7049-52. [PMID: 15473769 DOI: 10.1063/1.1807818] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The preparation of methyl iodide (CH(3)I) in selected rovibrational states [nu(7)=1 (C-H stretch); J] by infrared (IR) excitation prior to vacuum ultraviolet (VUV) photoionization has greatly simplified the observed pulsed field ionization-photoelectron (PFI-PE) spectra, allowing the direct determination of the rotational constants B(+)(C(+))=0.254+/-0.003 cm(-1) for CH(3)I(+)(X (2)E(3/2);nu(7) (+)) and the ionization energy (76 896.9+/-0.2 cm(-1)) for CH(3)I(+)(X (2)E(3/2);nu(7) (+)=1,J(+)=3/2)<--CH(3)I(X (1)A(1);nu(7)=1,J=0). The IR-VUV-PFI-PE and IR-VUV-photoion measurements also provide relative state-to-state (nu(7) (+)=1, J(+)<--nu(7)=1, J) cross sections for the photoionization process.
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Woo HK, Wang P, Lau KC, Xing X, Ng CY. Vacuum Ultraviolet (VUV) Pulsed Field Ionization−Photoelectron and VUV−IR Photoinduced Rydberg Ionization Study of trans-Dichloroethene. J Phys Chem A 2004. [DOI: 10.1021/jp040250s] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Woo HK, Wang P, Lau KC, Xing X, Ng CY. Single-photon vacuum-ultraviolet laser-pulsed-field ionization-photoelectron studies of trans- and cis-1-bromopropenes. J Chem Phys 2004; 120:9561-70. [PMID: 15267968 DOI: 10.1063/1.1718276] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The vacuum-ultraviolet (VUV) pulsed-field ionization-photoelectron (VUV-PFI-PE) spectra of trans-1-bromopropene (trans-CH(3)CH[Double Bond]CHBr) and cis-1-bromopropene (cis-CH(3)CH[Double Bond]CHBr) have been measured in the energy region of 74 720-76 840 cm(-1). The simulation of fine structures observed in the origin VUV-PFI-PE vibrational bands of these molecules has provided the ionization energies (IEs) of trans-1-bromopropene and cis-1-bromopropene to be 74 779.3+/-2.0 cm(-1) (9.2715+/-0.0002 eV) and 75 140.2+/-2.0 cm(-1) (9.3162+/-0.0002 eV), respectively. The vibrational bands resolved in these VUV-PFI-PE spectra at energies 0-1700 cm(-1) above the IEs of trans-1-bromopropene and cis-1-bromopropene have been assigned based on theoretical vibrational frequencies and calculated Franck-Condon factors for the ionization transitions.
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Woo HK, Wang P, Lau KC, Xing X, Ng CY. Vacuum ultraviolet-infrared photo-induced Rydberg ionization spectroscopy: C–H stretching frequencies for trans-2-butene and trichloroethene cations. J Chem Phys 2004; 120:1756-60. [PMID: 15268305 DOI: 10.1063/1.1634561] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
We have demonstrated the two-color vacuum ultraviolet (VUV)-infrared (IR) photoinduced Rydberg ionization (PIRI) experiment. Trichloroethene (ClCH=CCl2) and trans-2-butene (trans-CH3CH=CHCH3) were prepared in Rydberg states in the range of effective principal quantum number n* approximately 7-93 by VUV excitation prior to IR-induced autoionization. The observed VUV-IR-PIRI spectra are found to be independent of n*, suggesting that the electron Rydberg orbital is conserved, i.e., the Rydberg electron is behaving as a spectator during the excitation process. The observed IR active C-H stretching vibrational frequencies nu12+ = 3072+/-5 cm(-1) for ClCH=CCl2+ and nu23+ =2908+/-3 cm(-1), nu25+ =2990+/-10 cm(-1) and nu30+ =3022+/-10 cm(-1) for trans-CH3CH=CHCH3+ are compared with predictions based on ab initio quantum-chemical procedures and density functional calculations.
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Woo HK, Wang P, Lau KC, Xing X, Chang C, Ng CY. State-selected and state-to-state photoionization study of trichloroethene using the two-color infrared-vacuum ultraviolet scheme. J Chem Phys 2003. [DOI: 10.1063/1.1622932] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
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Li G, Chen X, Jang Y, Wang J, Xing X, Yang W, Hu Y. Obesity, coronary heart disease risk factors and diabetes in Chinese: an approach to the criteria of obesity in the Chinese population. Obes Rev 2002; 3:167-72. [PMID: 12164468 DOI: 10.1046/j.1467-789x.2002.00067.x] [Citation(s) in RCA: 95] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The aim of this work was to study the relationship between excess body weight and the risks of hypertension and diabetes in the population of northeastern China. Subsections of a cross-sectional survey in Da Qing City were used to assess the relationship of excess weight to risk factors for coronary heart disease (CHD). A 6-year prospective study also assessed the probability of developing Type 2 diabetes. A total of 2856 adults (25-70 years of age) were assessed cross-sectionally and 629 non-diabetic subjects of similar age were followed-up for 6 years. Blood pressure, plasma fasting glucose, triglycerides, high-density lipoporotein (HDL) cholesterol and fibrinogen levels were measured as well as weight, height and waist and hip circumferences. About 45% of adults had a body mass index (BMI) of > or =25.0. Risk factors increased with increasing BMI from a baseline value of 21.0: at a BMI of 23.0-24.9, the risk of hypertension and hypertriglyceridaemia doubled; the risk increased threefold at a BMI of 25.0-26.9. The prevalence of Type 2 diabetes increased progressively in women within the normal BMI range and in men from a BMI of 25.0. Type 2 diabetes was four times as common if the BMI was >27.0. Increasing waist measurements predicted 10-fold increases in hypertension and a three-to-five times increased risk of diabetes. Suitable waist cut-off points were 85cm for men and 80cm for women, with statistical analysis showing waist as the more dominant predictor of risk than age, waist-to-hip ratios or BMIs. Hence, small increases in BMI, and particularly in waist circumference, predict a substantial increase in the risk of diabetes and risk for CHD, especially hypertension, in Chinese adults.
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Green MP, Hanson KJ, Scherson DA, Xing X, Richter M, Ross PN, Carr R, Lindau I. In situ scanning tunneling microscopy studies of the underpotential deposition of lead on gold (111). ACTA ACUST UNITED AC 2002. [DOI: 10.1021/j100343a001] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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