395 results on '"Guo-Rong Chen"'
Search Results
302. Preparation of triazole-linked glycosylated α-ketocarboxylic acid derivatives as new PTP1B inhibitors
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Juan Xie, Guo-Rong Chen, Xiao-Peng He, Jia Li, Zhuo Song, Zhao-Xia Wang, Cui Li, Li-Xin Gao, and Yun Tang
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chemistry.chemical_classification ,Protein Tyrosine Phosphatase, Non-Receptor Type 1 ,Glycosylation ,Molecular Structure ,Chemistry ,Glycoconjugate ,Stereochemistry ,Organic Chemistry ,Triazole ,Carboxylic Acids ,General Medicine ,Triazoles ,Biochemistry ,Cycloaddition ,Analytical Chemistry ,chemistry.chemical_compound ,Structure-Activity Relationship ,Docking (molecular) ,Click chemistry ,Humans ,Glycosyl ,Enzyme Inhibitors ,Benzoic acid ,Acetophenone - Abstract
The synthesis of triazole-linked glycosyl acetophenone, benzoic acid, and α-ketocarboxylic acid derivatives was readily achieved via Cu(I)-catalyzed azide–alkyne cycloaddition (‘click’ reaction) in excellent yields of 93–97%. Among the synthesized glycoconjugates, the triazolyl α-ketocarboxylic acids were identified as the most potent protein tyrosine phosphatase 1B (PTP1B) inhibitors with micromole-ranged IC 50 values and moderate-to-good selectivity over a panel of homologous PTPs including TCPTP (4.6-fold), LAR (>30-fold), SHP-1 (>30-fold) and SHP-2 (>30-fold). Moreover, a docking simulation was conducted to propose a plausible binding mode of the glucosyl α-ketocarboxylic acid triazole with the enzymatic target. more...
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- 2010
303. ChemInform Abstract: Synthesis and Structure Determination of the First 1′-C-Cyano-β-D- Nucleosides
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Guo-Rong Chen, J. Le Quan Tuoi, V. Uteza, A. Grouiller, Gérard Descotes, and Bernard Fenet
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Chemistry ,Stereochemistry ,Nucleic acid ,General Medicine - Published
- 2010
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304. [Effects of ginkgo biloba extraction on contraction capacity of diaphragm from type 2 diabetic rats]
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Xu-sheng, Li, Yong-qiang, Fu, Biao, Zhou, Ye, Hu, and Guo-rong, Chen
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Male ,Rats, Sprague-Dawley ,Random Allocation ,Diabetes Mellitus, Type 2 ,Diaphragm ,Animals ,Ginkgo biloba ,Diabetes Mellitus, Experimental ,Drugs, Chinese Herbal ,Muscle Contraction ,Rats - Abstract
To investigate the effects of Ginkgo biloba extract (GbE) on the activities of energy metabolism enzymes and contraction capacity of diaphragm from type 2 diabetic rats.Forty SD male rats were randomly divided into normal control group (n=10) and model group (n=30). Type 2 diabetes models were induced by feeding with high-sucrose-high-fat diet and intraperitoneal injecting 25 mg/kg streptozotocin. 20 successful models were rearranged to two groups: diabetic group and GbE treatment group, 10 rats in each. Then the saline and 8 mg/(kg x d) of GbE were respectively intraperitoneal injected, once a day continuously for 8 weeks. Then diaphragm contractility was assessed using Peak twitch tension (Pt), Maximum tetanic tension (P0) and fatigue index (FI) in vitro diaphragm strip preparations. Cytochrome oxidase (CCO), lactate dehydrogenase (LDH) and succinate dehydrogenase (SDH) in diaphragm were detected and the varieties of diaphragm ultrastructure were observed.Compared with control group, Pt, P0 and FI in diabetic group decreased significantly (P0.01); the activity of CCO, LDH and SDH in the tissues was more obviously reduced than those in control group (P0.01). The ultrastructure in diabetic group under electron microscope indicated that diaphragm mitochondrions swelled and degenerated. The above changes were inhibited by GbE.GbE can enhance contraction capacity of diaphragm from type 2 diabetic rats by increasing the aerobic oxidation capacity, glycolytic capacity and the function of respiratory chain. more...
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- 2010
305. ChemInform Abstract: Phase-Transfer Catalyzed Enantioselective Epoxidation of Estra-Λ5(10),9(11)-diene Using Chiral Ammonium Salts Derived from Cinchona Alkaloids
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Yuanchao Li, Guo-Rong Chen, Yaxi Yang, and Zheng Li
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chemistry.chemical_compound ,chemistry ,Diene ,Phase (matter) ,Enantioselective synthesis ,Organic chemistry ,Ammonium ,General Medicine ,Cinchona Alkaloids ,Catalysis - Abstract
A series of chiral ammonium salts derived from cinchona alkaloids is synthesized and used as phase-transfer catalyst to improve the epoxidation of title compound (I).
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- 2010
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306. [Primary malignant rhabdoid tumor of rectum: report of a case]
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Hai-hong, Zheng, Liang, Wu, and Guo-rong, Chen
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Adult ,Diagnosis, Differential ,Young Adult ,Rectal Neoplasms ,Lymphatic Metastasis ,Mucin-1 ,Synaptophysin ,Humans ,Keratins ,Vimentin ,Female ,Sarcoma ,Rhabdoid Tumor - Published
- 2010
307. Perinatal exposure to di-(2-ethylhexyl) phthalate leads to restricted growth and delayed lung maturation in newborn rats
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Jin-Ni Chen, Jing Lin, Hai-Shan Wu, Zhen-Lang Lin, Guo-Rong Chen, Shangqin Chen, Ren-Shan Ge, Yuan Gao, and Xiao-Hong Cai
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Male ,endocrine system ,medicine.medical_specialty ,Intrauterine growth restriction ,Gene Expression ,Rats, Sprague-Dawley ,chemistry.chemical_compound ,Fetal Organ Maturity ,Plasticizers ,Pregnancy ,Internal medicine ,Diethylhexyl Phthalate ,11-beta-Hydroxysteroid Dehydrogenase Type 1 ,medicine ,Animals ,Pulmonary surfactant-associated protein B ,Neonatology ,Respiratory system ,Lung ,DNA Primers ,Pulmonary Surfactant-Associated Protein B ,Perinatal Exposure ,Base Sequence ,Pulmonary Surfactant-Associated Protein A ,business.industry ,Respiration ,Phthalate ,Obstetrics and Gynecology ,medicine.disease ,Rats ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Animals, Newborn ,Prenatal Exposure Delayed Effects ,Pediatrics, Perinatology and Child Health ,Gestation ,Female ,business - Abstract
Background: Pregnant women and infants have significant exposures to the most commonly used plasticizer di-(2-ethylhexyl) phthalate (DEHP). Objectives: This study was designed to evaluate the effects of DEHP exposure on growth and lung maturation in rats and determine if DEHP regulation of 11 β-hydroxysteroid dehydrogenase type 1 gene (Hsd11b1) expression in the lung tissue plays a role in its effects on lung maturation. Method: Pregnant Sprague-Dawley rats were treated from gestational day 12 to postnatal day (PND) 21 with DEHP orally at dosages of 0, 10, 100 or 750 mg/kg/day, respectively (n=8 for each group). Two rat pups (one male and one female) from each litter were sacrificed at PND 1 and 21. Body weight was measured and the lung was processed for histology and calculation of lung interstitial tissue proportion as well as real-time PCR determination of the expressions of Hsd11b1, surfactant associated protein-A1 gene (Sftpa1) and B gene (Sftpb). Results: The perinatal DEHP exposure led to a dose dependent intrauterine and postnatal growth restriction (P < 0.001). High dose DEHP (750 mg/kg/day) exposure led to decreased gas-exchange space as evidenced by increased lung interstitial tissue proportion (P < 0.001), but did not cause significant changes in Hsd11b1, Sftpa1 or Sftpb gene expression in the rat lung at PND 1. The DEHP-induced change in lung histology remained significant at PND 21 with improvement despite continual exposure to DEHP. Conclusion: Perinatal DEHP exposure leads to growth restriction and delayed lung maturation in newborn rats. more...
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- 2010
308. An industrial wastewater pollution degree evaluation method based on improved fuzzy evaluation theories
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Liang Lei, Guo-rong Chen, Juli Deng, Qian Xiong, and Jinliang Shi
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Pollution ,Computer science ,media_common.quotation_subject ,Fuzzy set ,Environmental engineering ,Industrial pollution ,Fuzzy logic ,Industrial waste ,Weighting ,Industrial wastewater treatment ,Risk analysis (engineering) ,Wastewater ,Evaluation methods ,Sewage treatment ,Intelligent control ,media_common - Abstract
The evaluation of industrial wastewater pollution levels is the prerequisite for pollution control, and in some case, we need to focus our attentions on some key factors. But the classical fuzzy evaluation method had some limitations to resolve this kind of pollution levels evaluation problem. In the paper, we analyzed the classical fuzzy evaluation method to find the shortcomings of the method firstly, and then improved the fuzzy evaluation method by changing the weighting of the factors in order to highlight the key factors. The result of cases studied shows that the method presented in this paper is more reasonable to the problem. more...
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- 2010
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309. ChemInform Abstract: A Stereocontrolled Radical Access to C-Allyl β-D-Glycopyranosides from Glycopyranosylidene Dihalides Found En Route to C-Glycodienes
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Joëlle Gola, Christophe Raphoz, Georg Hetzer, Guo-Rong Chen, and Jean-Pierre Praly
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chemistry.chemical_classification ,Chemistry ,Hydride ,Glycoside ,General Medicine ,Medicinal chemistry - Abstract
Application of the Keck reaction to peracetylated glycopyranosylidene dihalides under mild conditions led efficiently to chloro C-allyl glycosides which were converted to either the corresponding C-allyl β-D-glycosides of C-D-glycodienes on treatment with, respectively, tri-n-butyltin hydride and DBU. more...
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- 2010
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310. ChemInform Abstract: Ring-Closing Olefin Metathesis of 3,3′-(D-Glycopyranosylidene)bis(1-propene) Compounds as a Route to Anomeric Spiro Sugars
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Guo-Rong Chen, Joëlle Gola, Michaela Steng, Zhong Bo Fei, Yu-Yuan Xie, Jin-Lou Xu, Xiao-Ting Huang, and Jean-Pierre Praly
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Propene ,chemistry.chemical_compound ,Elimination reaction ,Anomer ,Chemistry ,Yield (chemistry) ,Salt metathesis reaction ,General Medicine ,Ring (chemistry) ,Sugar ,Medicinal chemistry ,Catalysis - Abstract
New peracetylated 3,3′-(D-glycopyranosylidene)bis(1-propene), prepared from peracetylated anomeric sugar dihalides and allyltributyltin in excess under UV irradiation conditions (AIBN, ca. 35 °C), lent themselves to ring-closing olefin metathesis in the presence of Grubbs’ catalyst (6 mol %) to afford the corresponding peracetylated spiro[1,5-anhydro-D-glycopyranositol-1,4′-cyclopent-1′-enes] (D-gluco: 81%, D-manno: 89%, D-galacto: 72% isolated yield), which could be deacetylated quantitatively. The bis(allylation) reaction (D-gluco: 40%, D-manno: 34%, D-galacto: 24% isolated yield) was in competition with radical-induced rearrangement and elimination reactions. The last process, found to be favored at higher temperature (80 °C), opens an easy route to sugar dienes difficult to prepare otherwise. more...
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- 2010
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311. INFLUENCE OF TYPHOON CHARACTERISTICS ON FLOOD FORECASTING
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Guo-Rong Chen, Pei-Yu Huang, and Gwo-Fong Lin
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Meteorology ,Typhoon ,Flood forecasting ,Environmental science - Published
- 2010
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312. [The relationship between the expression of NF-kB, TGFbeta1, FN and hepatic fibrosis in diabetic rats]
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Rong-Rong, Wang, Xiang-Yi, Chen, Hong-Li, Liao, Li, Wan, Jian-Min, Li, Li-Ling, Chen, Xiao-Fei, Chen, and Guo-Rong, Chen
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Liver Cirrhosis ,Male ,Rats, Sprague-Dawley ,Transforming Growth Factor beta1 ,Diabetes Mellitus, Type 2 ,Liver ,NF-kappa B ,Animals ,Diabetes Mellitus, Experimental ,Fibronectins ,Rats - Abstract
To investigate the expression of nuclear factor kappa B (NF-kB), transforming growth factor beta1 (TGFbeta1), fibronectin (FN) in liver from diabetic rats.Twenty male Sprague-Dawley rats were divided randomly into two groups: normal control group (n = 10) and type 2 diabetic group (n = 10). After 4 weeks of high-fat feeding, diabetic group rats were injected with low dosage streptozotocin (30 mg/kg) intraperitoneally to induce type 2 diabetic rat models. The diabetic rats received high-fat feeding for another 12 weeks. At the end of the experiment, the fibrosis lesion was observed under light microscopy after Masson staining. The mRNA levels of NF-kB, TGFbeta1, FN from rats liver were assayed by semi-quantity RT-PCR, the protein levels of NF-kB, TGFbeta1, FN was detected by IHC.Fibrosis was found in diabetic rats. The levels of TGFbeta1, FN mRNA in liver tissues increased in diabetic rats compared with normal control rats (0.91+/-0.19 vs 0.47+/-0.20, t = 5.233, P less than 0.05; 1.85+/-0.70 vs 1.22+/-0.39, t = 2.463, P less than 0.05). And the protein levels of NF-kB P65, TGFbeta1, FN in liver tissues from diabetic rats were significantly higher than those in normal control rats (10978.77+/-8782.59 vs 4206.86+/-1430.56, Z = 1.979, P less than 0.05; 8551.00+/-4768.68 vs 4036.85+/-1051.12, Z = 2.303, P less than 0.05; 16980.30+/-11529.29 vs 5701.95+/-9461.75, t = -2.391, P less than 0.05).Upregulation of NF-kB, TGFbeta1, FN in liver tissues may play a role in the hepatic fibrogenesis in diabetic rats. more...
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- 2010
313. ChemInform Abstract: Infrared Luminescence of Tm3+-Doped Chalcohalide Glasses in GeS2-In2Se3-CsBr System
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Guo-Rong Chen, Ce Shen, Huidan Zeng, Wei Wang, Qiqi Yan, and Yinsheng Xu
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Chalcogen ,Infrared ,Chemistry ,Doping ,General Medicine ,Photochemistry ,Luminescence - Published
- 2010
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314. Energy Transfer and Photoluminescence of Zinc Phosphate Glasses Co-Doped with Tb3+and Mn2+
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Shufen Wang, Zhongwen Xing, Xiaoluan Liang, Zhaosong Zou, Yinyao Liu, and Guo-Rong Chen
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Photoluminescence ,Materials science ,Energy transfer ,Inorganic chemistry ,Doping ,Analytical chemistry ,Zinc phosphate ,Ion ,chemistry.chemical_compound ,chemistry ,Materials Chemistry ,Ceramics and Composites ,Emission spectrum ,Spectroscopy ,Excitation - Abstract
Tb3+–Mn2+-codoped zinc–strontium–phosphate glasses are prepared by the conventional melt-quenching method, and their photoluminescence spectroscopy is investigated as a function of the Mn2+ concentration. It is observed that the excitation band at 350 nm due to Tb3+ overlaps that of Mn2+ ions, thus suitable for efficiently activating Tb3+–Mn2+-codoped glasses. The emission spectra of codoped glasses simultaneously show the blue (486 nm), green (541 and 582 nm), and red (617 nm) emissions. The 590 nm broad emissions of Mn2+ ions have been enhanced with the doping of Tb3+ ions, while the Tb3+ emissions have decreased with the increasing concentration of Mn2+. Decay curves of Tb3+ ions with the different concentrations of Mn2+ ions are also studied. The possible energy transfer process from Tb3+ to Mn2+ ions is proposed and the relevant mechanism is discussed. more...
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- 2010
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315. Effective forecasting of hourly typhoon rainfall using support vector machines
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Yang-Ching Chou, Guo-Rong Chen, Ming-Chang Wu, and Gwo-Fong Lin
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Meteorology ,Artificial neural network ,Warning system ,Computer science ,business.industry ,Generalization ,Machine learning ,computer.software_genre ,Fuzzy logic ,Backpropagation ,Support vector machine ,Typhoon ,Artificial intelligence ,business ,computer ,Lead time ,Water Science and Technology - Abstract
[1] Typhoon rainfall is one of the most difficult elements of the hydrologic cycle to forecast because of the high variability in space and time and the complex physical process. To obtain more effective forecasts of hourly typhoon rainfall, novel models with better ability are desired. On the basis of support vector machines (SVMs), which are a novel kind of neural networks (NNs), effective hourly typhoon rainfall forecasting models are constructed. As compared with backpropagation networks (BPNs), which are the most frequently used conventional NNs, SVMs have three advantages: (1) SVMs have better generalization ability, (2) the architectures and the weights of the SVMs are guaranteed to be unique and globally optimal, and (3) SVM is trained much more rapidly. An application is conducted to clearly demonstrate these three advantages. The results indicate that the proposed SVM-based models are better performed, robust, and efficient than the existing BPN-based models. To further improve the long lead time forecasting, typhoon characteristics are added as key input to the proposed models. The comparison between SVM-based models with and without typhoon characteristics confirms the significant improvement in forecasting performance due to the addition of typhoon characteristics for long lead time forecasting. The proposed SVM-based models are recommended as an alternative to the existing models. The proposed modeling technique is also expected to be useful to support reservoir operation systems and flood, landslide, debris flow, and other disaster warning systems. more...
- Published
- 2009
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316. Research on idle speed control for EFI gasoline engine with ETB
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Qian Xiong, Zeng Peng, Guo-rong Chen, and Jin-liang Shi
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business.industry ,Computer science ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,Throttle ,Automotive engineering ,Vehicle dynamics ,Internal combustion engine ,Embedded system ,Spark (mathematics) ,Idle speed ,Torque ,business ,Engine control unit ,Petrol engine - Abstract
This paper researches on some factors that can control engine speed and develop algorithm to control the engine idle speed. By managing the intake air mass and spark advance angle together, this algorithm can make the engine running as stable as possible. Experiments on one vehicle which adopt the electronic control throttle body show that the new control algorithm provides good idle speed control. more...
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- 2009
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317. ChemInform Abstract: Free Radical and Ionic Routes Toward Hydrolytically Stable and Bioactive C-Glycosyl Compounds
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Jean-Pierre Praly and Guo-Rong Chen
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chemistry.chemical_compound ,Chemistry ,Organic chemistry ,Ionic bonding ,Glycosyl ,General Medicine - Published
- 2009
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318. In Utero and Lactational Exposures to Diethylhexyl-Phthalate Affect Two Populations of Leydig Cells in Male Long-Evans Rats1
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Yuan Jin, Zhongqiu Lu, Chantal M. Sottas, Guo-Rong Chen, Dianne O. Hardy, Matthew P. Hardy, Ren-Shan Ge, Qing-Quan Lian, Han Lin, Guo-Xin Hu, and Yunhui Zhang
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Male ,medicine.medical_specialty ,endocrine system ,medicine.drug_class ,Gene Expression ,Biology ,Antiandrogen ,chemistry.chemical_compound ,Fetus ,Plasticizers ,Pregnancy ,Internal medicine ,Diethylhexyl Phthalate ,medicine ,Animals ,Lactation ,Rats, Long-Evans ,Testosterone ,RNA, Messenger ,reproductive and urinary physiology ,Leydig cell ,luteinizing hormone/choriogonadotropin receptor ,Phthalate ,Leydig Cells ,Cell Biology ,General Medicine ,Rats ,Endocrinology ,medicine.anatomical_structure ,Reproductive Medicine ,chemistry ,In utero ,Maternal Exposure ,Female ,Gonadotropin ,Luteinizing hormone ,Research Article - Abstract
Diethylhexylphthalate (DEHP) has been classified as an antiandrogen. However, whether in utero and lactational exposures of DEHP affect Leydig cells has not been well established. In the present study, the effects of DEHP exposures on fetal Leydig cells (FLCs) and adult Leydig cells (ALCs) were assessed. Pregnant dams of Long-Evans rats were treated with 0, 10, and 750 mg/kg body weight DEHP from Gestational Day 12.5 to Postnatal Day (PND) 21.5. Fetal Leydig cell clustering and FLC-specific gene expression were examined. Anogenital distances (AGDs) of male pups were assessed at PND 2. Serum testosterone levels of male pups and mRNA levels of ALC-specific genes were measured at PNDs 21 and 49. The AGDs of male pups were significantly shorter in the group treated with 750 mg/kg DEHP (mean +/- SEM, 3.68 +/- 0.16 mm) compared with control (4.62 +/- 0.13 mm). The FLCs were aggregated after 10 and 750 mg/kg DEHP exposures. Several FLC-specific genes, including luteinizing hormone receptor (Lhcgr) and steroidogenic enzyme genes, were downregulated at both doses. Serum testosterone levels were significantly lower compared with control at PND 21 after treatment of 10 or 750 mg/kg DEHP, and continued to be lower even up to 49 days postpartum at the higher dose. The mRNA levels for Lhcgr and steroidogenic enzyme genes were significantly lower at both doses of DEHP at PND 21, whereas there were no significant differences for these genes at PND 49. In conclusion, in utero and continued lactational exposures to DEHP exert long-term disruption of steroidogenesis of ALCs. more...
- Published
- 2009
319. Electronic Throttle Control Strategy Develop
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Guo-rong Chen, Jin-liang Shi, and Qian Xiong
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Internal combustion engine ,Computer science ,Control theory ,Loop control ,Airflow ,Oscillation (cell signaling) ,PID controller ,Throttle ,Work environment ,Electronic throttle control - Abstract
This paper researches on how to improve the ETB (Electronic Throttle Body) performance, as the emission requirement becomes more and more strict this core function’s performance becomes more and more important. We can get the command throttle position easy but there are many factors can affect the ETB intake air mass model in the real work environment, such as engine oscillation, intake air flow disturbance and motor aging and so on. We must build close loop control which should detect the condition change and correct plate open angle to improve the ETB work performance. more...
- Published
- 2009
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320. Construction of design hyetographs for locations without observed data
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Guo-Rong Chen, Shen-Jung Liu, Gwo-Fong Lin, and Ming-Chang Wu
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Self-organizing map ,Artificial neural network ,Computer science ,Salient ,Kriging ,Robustness (computer science) ,Hyetograph ,Data mining ,computer.software_genre ,Cluster analysis ,computer ,Spatial analysis ,Water Science and Technology - Abstract
A design hyetograph which represents the time distribution of design rainfall depth corresponding to a duration and a return period is essential in hydrologic design. However, for locations without observed data (ungauged sites), construction of design hyetographs is a difficult task because of the lack of data. Hence, an approach based on self-organizing map (SOM) is proposed in this paper to construct design hyetographs at ungauged sites. SOM, which is a special kind of artificial neural networks (ANNs), is a powerful technique for extracting and visualizing salient features of data and for solving classification problems. The proposed approach is composed of three steps: classification, assignment and construction. First, the SOM-based classification is performed to analyse gauged sites' design hyetographs. Second, based on the concept of indicator kriging, a method is developed to assign an ungauged site of interest to a certain cluster. Third, based on the spatial information, the clustering results, and the design hyetographs of gauged sites, the design hyetograph at the site of interest is constructed using the reciprocal-distance-squared method. An application is conducted to assess the advantages of the proposed approach over the conventional approaches. Moreover, cross-validation tests are applied to evaluate the performance of the accuracy and the robustness of the proposed approach. The results confirm the improvement in performance by using the proposed approach instead of conventional approaches. The proposed approach is useful for constructing design hyetographs at ungauged sites. Copyright © 2009 John Wiley & Sons, Ltd. more...
- Published
- 2009
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321. Study on Gasoline Engine Misfiring Detection Using the CPS Signal
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Jin-liang Shi, Guo-rong Chen, and Qian Xiong
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Crank ,ALARM ,On-board diagnostics ,Engine braking ,Computer science ,Torque ,Algorithm design ,Signal ,Simulation ,Automotive engineering ,Petrol engine - Abstract
As one of the homologation test item, the misfiring detection and alarm function is one of the base function of OBD (On Board Diagnostics). This paper researches on how to use the crank position signal to detect the misfiring happen or not and how to alarm which are enforced by the OBD requirements. Because the engine becomes more and more advance and most of the engine control strategies base on the torque control model, most of vehicle need engine brake function. The problem is that with the engine brake function some big deceleration is the driver command not caused by the misfiring, this paper introduces the algorithm design for the misfiring for this kind of engine work. At the last of this paper the authors validate the method on a 2.0L 4 cylinders engine. more...
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- 2009
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322. An Evolvement-Based Modeling Method for Logistics Network
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Jun Zou, Guo-rong Chen, Juli Deng, Qian Xiong, and Shan Huang
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Structure (mathematical logic) ,Order (exchange) ,Computer science ,Process (engineering) ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,Context (language use) ,Industrial engineering ,Term (time) - Abstract
In order to simulate the development process of logistics network, an evolvement method for logistics network is put out. The logistics network’s growth and degeneration are all been taken into consideration firstly, based on the dissipation characters of the network, the dynamics of logistics network is been brought forward then. The simulating results support the modeling method come context and fit the demands of real logistics network, the changing of nodes and edges can’t destroy the hierarchical structure and the dissipative structure. The modeling method affords a new way to us to analyze the logistics network from the system term. more...
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- 2009
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323. ChemInform Abstract: C-D-Glucopyranosyl Derivatives of Tocopherols - Synthesis and Evaluation as Amphiphilic Antioxidants
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Claire Dufour, Guo-Rong Chen, Olivier Dangles, Stéphanie Galland, Jean-Pierre Praly, Li He, and Bernard Fenet
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carbohydrates (lipids) ,chemistry.chemical_compound ,Phytol ,Electrophilic substitution ,chemistry ,Linoleic acid ,Amphiphile ,Moiety ,Organic chemistry ,Alcohol ,General Medicine ,Ceric ammonium nitrate ,Micelle - Abstract
Treatment of dimethylhydroquinone dimethyl ethers (ortho and meta isomers) with glycopyranose pentaacetates (D-gluco, D-galacto) in the presence of SnCl4 and F3CCO2Ag selectively afforded the corresponding C-β-D-glycosyl derivatives by aromatic electrophilic substitution. Oxidation of the dimethoxybenzene moiety with ceric ammonium nitrate delivered C-β-D-glycosyl-dimethylbenzoquinones, which were reduced with Na2S2O4 to the corresponding C-β-D-glycosyl-dimethylhydroquinones. ZnCl2-catalyzed cyclization either with methylbut-2-en-1-ol (prenyl alcohol) or with all-racemic phytol led to acetyl-protected C-β-D-glycosyl chromanols or C-β-D-glycosyl tocopherols, the sugar residues of which were deacetylated under base catalysis conditions. These new molecules were evaluated as antioxidants in terms of their ability to inhibit the peroxidation of linoleic acid in SDS micelles. The position of the C-glucosyl moiety on the phenolic nucleus emerges as the critical structural determinant of their activity. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008) more...
- Published
- 2008
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324. [Ginkgo biloba extract enhances testosterone synthesis of Leydig cells in type 2 diabetic rats]
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Xiao-Ye, Wu, Wen-Yan, Wang, Rong-Rong, Wang, Lin, Xie, Zhou-Xi, Fang, and Guo-Rong, Chen
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Male ,17-Hydroxysteroid Dehydrogenases ,Plant Extracts ,Reverse Transcriptase Polymerase Chain Reaction ,Hydroxysteroid Dehydrogenases ,Gene Expression ,Ginkgo biloba ,Leydig Cells ,Enzyme-Linked Immunosorbent Assay ,Luteinizing Hormone ,Phosphoproteins ,Rats ,Rats, Sprague-Dawley ,Diabetes Mellitus, Type 2 ,Microscopy, Electron, Transmission ,Animals ,Testosterone ,Cholesterol Side-Chain Cleavage Enzyme ,RNA, Messenger - Abstract
To investigate the effects of Ginkgo biloba extract (EGB) on the testosterone synthesis in the Leydig cells of type 2 diabetic rats.Thirty male SD rats were equally randomised into a normal control, a type 2 diabetic and an EGB group. Morphological changes of Leydig cells were observed by light microscopy (LM) and transmission electron microscopy (TEM), concentrations of serum luteinizing hormone (LH) and testosterone (T) were determined by enzyme linked immunosorbent assay (ELISA), and the mRNA levels in the steroidogenic acute regulatory protein (StAR), cytochrome P450 side chain cleavage (P450scc), cytochrome P450 17a-hydroxylase (P450c17), 17beta-hydroxysteroid dehydrogenase 3 (17beta-HSD3) and 3beta-hydroxysteroid dehydrogenase (3beta-HSD1) from the Leydig cells were examined by RT-PCR.Compared with the normal control, there was a significant decrease in the number and volume of Leydig cells, the levels of serum LH and T and the expression of mRNA in StAR, P450scc, 17beta-HSD3 and 3beta-HSD1 in the type 2 diabetes group. And the expression of the P450c17 gene showed a tendency of descending, but with no significance. Compared with the type 2 diabetes group, 12 weeks of EGB treatment caused very slight pathological changes in the Leydig cells, significantly increased the concentrations of blood LH and T, markedly elevated the levels of mRNA in StAR and P450scc and induced an ascending tendency of the expressions of P450c17, 17beta-HSD3 and 3beta-HSD1.EGB enhances testosterone synthesis and secretion of Leydig cells by reducing the impairment of the testis in type 2 diabetic rats. more...
- Published
- 2008
325. Involvement of testicular growth factors in fetal Leydig cell aggregation after exposure to phthalate in utero
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Lei Dong, Ren-Shan Ge, Han Lin, Chantal M. Sottas, Qingquan Lian, Matthew P. Hardy, Li Xiaokun, Guo-Xin Hu, Dianne O. Hardy, and Guo-Rong Chen
- Subjects
Male ,medicine.medical_specialty ,endocrine system ,Biology ,Leukemia Inhibitory Factor ,chemistry.chemical_compound ,Pregnancy ,Internal medicine ,hemic and lymphatic diseases ,Diethylhexyl Phthalate ,medicine ,Animals ,Rats, Long-Evans ,RNA, Messenger ,Insulin-Like Growth Factor I ,Testosterone ,Stem Cell Factor ,Multidisciplinary ,Leydig cell ,Phthalate ,Gene Expression Regulation, Developmental ,Leydig Cells ,Biological Sciences ,Cell aggregation ,Rats ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Endocrine disruptor ,In utero ,Maternal Exposure ,Pregnancy, Animal ,Female ,Reproductive toxicity ,Corn oil - Abstract
Exposures to di-(2-ethylhexyl) phthalate (DEHP) have been shown to be associated with decreased adult testosterone (T) levels and increased Leydig cell numbers. As yet, little is known about DEHP effects in utero on fetal Leydig cells (FLC). The present study investigated effects of DEHP on FLC function. Pregnant Long–Evans female rats received vehicle (corn oil) or DEHP at 10, 100, or 750 mg/kg by oral gavage from gestational day (GD)2–20. At GD21, T production, FLC numbers and distribution, and testicular gene expression were examined. The percentage of FLC clusters containing 6–30 cells increased in all treatment groups, with 29 ± 2% in control vs. 37 ± 3, 35 ± 3, and 56 ± 4% in rats receiving 10, 100, and 750 mg/kg DEHP, respectively. In contrast, FLC numbers were 33% and 39% lower than control after exposures to 100 and 750 mg/kg DEHP, respectively. At these doses, mRNA levels of leukemia inhibitory factor (LIF) increased. LIF was found to induce cell aggregation in FLCs in vitro , consistent with the hypothesis that DEHP induced FLC aggregation. Testicular T levels were doubled by the 10 mg/kg dose and halved at 750 mg/kg. The mRNA levels of IGF-1 and c- Kit ligand (KITL) were induced by 10 mg/kg DEHP. These results, taken together, indicate that fetal exposures to DEHP have effects on FLC number, distribution, and most importantly, steroidogenic capacity and suggest that abnormal expressions of IGF1, KITL, and LIF genes may contribute to the reproductive toxicity of phthalates. more...
- Published
- 2008
326. ChemInform Abstract: AIBN-Initiated Radical Addition of gem-Difluorinated Alkyl Iodides to Alkynes and the Pd-Catalyzed Sonogashira Coupling Reaction of (E)-Phenyl Difluoromethylene Vinylic Iodides with Terminal Alkynes
- Author
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Xianjin Yang, Xueyan Yang, Xiang Fang, Guo-Rong Chen, Fanhong Wu, Shenjie Mao, and Zhonghua Wang
- Subjects
chemistry.chemical_classification ,Addition reaction ,chemistry ,Sonogashira coupling ,chemistry.chemical_element ,Organic chemistry ,Stereoselectivity ,General Medicine ,Medicinal chemistry ,Alkyl ,Coupling reaction ,Catalysis ,Palladium - Abstract
The addition of gem-difluorinated alkyl iodides to alkynes initiated by AIBN neatly gave the corresponding difluoromethylene vinyl iodides among which the stereoselectivity of aromatic acetylenes was high. The further coupling reaction of E-phenyl difluoromethylene vinyl iodides with terminal alkynes in the presence of catalytic palladium afforded the substituted difluorinated enynes. more...
- Published
- 2008
- Full Text
- View/download PDF
327. [Relationship between phthalates and testicular dysgenesis syndrome]
- Author
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Guo-Rong, Chen, Lei, Dong, Ren-Shan, Ge, and Matthew P, Hardy
- Subjects
Adult ,Male ,Infant, Newborn ,Phthalic Acids ,Leydig Cells ,Syndrome ,Gonadal Dysgenesis ,Testicular Diseases ,Fetus ,Maternal Exposure ,Pregnancy ,Cryptorchidism ,Testis ,Humans ,Female ,Infertility, Male - Abstract
Recent epidemiological evidence demonstrates that boys born to women exposed to phthalates during pregnancy have an increased incidence of cryptorchidism, hypospadias, testicular cancer and spermatogenic dysfunction, which are collectively referred to as testicular dysgenesis syndrome (TDS). TDS may be attributed to the dysfunction of Leydig cells and Sertoli cells during their differentiation after exposure to phthalates in utero. Fox example, Leydig cell functions are significantly affected by phthalates, leading to the decrease of two Leydig cell products--insulin-like growth factor 3 (INSL3) and testosterone, which are critical factors for testis descent. The disorientation of Leydig cells and Sertoli cells in the adult testis may be the cause of spermatogenic dysfunction. more...
- Published
- 2007
328. Palladium-Catalyzed Arylation of α,α-Difluoro-allylic-β-hydroxyester
- Author
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Xiang Fang, Min Zhao, Guo-Rong Chen, Xianjin Yang, Fanhong Wu, and Xueyan Yang
- Subjects
chemistry.chemical_classification ,Base (chemistry) ,Chemistry ,Aryl ,Organic Chemistry ,General Medicine ,Biochemistry ,Medicinal chemistry ,Coupling reaction ,Catalysis ,chemistry.chemical_compound ,Drug Discovery ,Organic chemistry ,Base (exponentiation) - Abstract
The aryl-substituted α,α-difluoro-allylic-β-hydroxyesters and aryl-substituted α,α-difluoroketones were obtained via the coupling reaction of aryl iodides with α,α-difluoro-allylic-β-hydroxyester in the presence of Pd(OAc)2 as the catalyst and Et3N as the base. more...
- Published
- 2007
- Full Text
- View/download PDF
329. Graphene Composites: Simultaneous Detection of Diverse Glycoligand-Receptor Recognitions Using a Single-Excitation, Dual-Emission Graphene Composite (Adv. Funct. Mater. 23/2015)
- Author
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He Tian, Xiao-Peng He, Ding-Kun Ji, and Guo-Rong Chen
- Subjects
Biomaterials ,Materials science ,Graphene ,law ,Dual emission ,Composite number ,Electrochemistry ,Nanotechnology ,Condensed Matter Physics ,Single excitation ,Electronic, Optical and Magnetic Materials ,law.invention - Published
- 2015
- Full Text
- View/download PDF
330. Correction: Glycosylation enhances the aqueous sensitivity and lowers the cytotoxicity of a naphthalimide zinc ion fluorescence probe
- Author
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Lei Dong, Yi Zang, Dan Zhou, Xiao-Peng He, Guo-Rong Chen, Tony D. James, and Jia Li
- Subjects
Materials Chemistry ,Metals and Alloys ,Ceramics and Composites ,General Chemistry ,Catalysis ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials - Abstract
Correction for ‘Glycosylation enhances the aqueous sensitivity and lowers the cytotoxicity of a naphthalimide zinc ion fluorescence probe’ by Lei Dong et al., Chem. Commun., 2015, DOI: 10.1039/c5cc04357c. more...
- Published
- 2015
- Full Text
- View/download PDF
331. Phthalate ester toxicity in Leydig cells: developmental timing and dosage considerations
- Author
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Ren-Shan Ge, Matthew P. Hardy, Guo-Rong Chen, and Cigdem Tanrikut
- Subjects
Male ,endocrine system ,medicine.medical_specialty ,medicine.drug_class ,Biology ,Testicle ,Toxicology ,Antiandrogen ,Gonadal Dysgenesis ,chemistry.chemical_compound ,Mice ,Plasticizers ,Pregnancy ,Internal medicine ,Diethylhexyl Phthalate ,medicine ,Endocrine system ,Animals ,Testicular cancer ,Fetus ,Leydig cell ,Molecular Structure ,Phthalate ,Leydig Cells ,medicine.disease ,Rats ,medicine.anatomical_structure ,Endocrinology ,chemistry ,Maternal Exposure ,Toxicity ,Female - Abstract
Humans have significant exposures to phthalates, as these chemical plasticizers are ubiquitously present in flexible plastics. Recent epidemiological evidence indicates that boys born to women exposed to phthalates during pregnancy have an increased incidence of congenital genital malformations and spermatogenic dysfunction, signs of a condition referred to as testicular dysgenesis syndrome (TDS). TDS is thought to develop as a result of environmental factors that cause a testicular disturbance at an early fetal stage with a resultant spectrum of clinical testicular dysfunction, ranging from impaired spermatogenesis and genital malformations to increased risk for development of testicular cancer. Proposed environmental factors in the etiology of TDS include endocrine disrupting compounds such as the phthalates. Leydig cells have been classified as one of the main targets for phthalate ester toxicity in the body based on studies in rodents. In support of this hypothesis, two Leydig cell products - insulin-like growth factor 3 (INSL3) and testosterone (T) - are both suppressed after phthalate exposures. Both fetal and adult generations of Leydig cells are affected by phthalate esters, although their sensitivities may differ. In rodent models, when pregnant dams are exposed to phthalate esters, fetal Leydig cells form enlarged clusters that are retained in the testis even after birth, in contrast to untreated controls. Despite the retention of fetal Leydig cells, however, their numbers and average cell volume of total in exposed males are reduced, as are INSL3 production and steroidogenic competence. These alterations are directly associated with clinical features of TDS, including cryptorchidism and impaired spermatogenesis. more...
- Published
- 2006
332. Adult hippocampal ganglioneuroblastoma: Case report and literature review.
- Author
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Pei-Sen Yao, Guo-Rong Chen, Huang-Cheng Shang-Guan, Qing-Song Lin, Xing-Fu Wang, Shu-Fa Zheng, De-Zhi Kang, Yao, Pei-Sen, Chen, Guo-Rong, Shang-Guan, Huang-Cheng, Lin, Qing-Song, Wang, Xing-Fu, Zheng, Shu-Fa, and Kang, De-Zhi more...
- Published
- 2017
- Full Text
- View/download PDF
333. Irradiation effects on glasses containing ZnO as emission centers
- Author
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Stefania Baccaro, Y. Yunxia, X. Fang, Z. Donghui, Z. Junbiao, Guo-Rong Chen, and Angelica Cecilia
- Subjects
Nuclear and High Energy Physics ,Materials science ,Dopant ,business.industry ,Band gap ,Doping ,Wide-bandgap semiconductor ,Analytical chemistry ,Radiation ,medicine.disease_cause ,Spectral line ,Ultraviolet visible spectroscopy ,Nuclear Energy and Engineering ,Radiation damage ,medicine ,Optoelectronics ,Irradiation ,Electrical and Electronic Engineering ,business ,Spectroscopy ,Radiation resistance ,Ultraviolet - Abstract
ZnO-based silicate glasses are studied in the present paper. Irradiation resistance of glass samples is tested under the /sup 60/Co /spl gamma/-ray radiation at the doses of 71 and 262 Gy. Ultraviolet and visible transmission spectra of glass samples are compared before and after irradiation treatment. Test results show that radiation damage of ZnO-based glasses increases with dose while the glass with the Al/sub 2/O/sub 3/ donor dopants exhibits improved radiation resistance. The latter can be correlated to bandgap broadening effect due to Al/sub 2/O/sub 3/ doping in the ZnO-based glass and to the role of Al/sup 3+/ as the network intermediate to enter partially the tetrahedral structure of silicate glass. more...
- Published
- 2005
- Full Text
- View/download PDF
334. Optical characterisation under irradiation of Ce/sup 3+/(Tb/sup 3+/)-doped phosphate scintillating glasses
- Author
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Stefania Baccaro, Angelica Cecilia, Alessia Cemmi, M Niki, Guo-Rong Chen, and E. Mihokova
- Subjects
Nuclear and High Energy Physics ,Materials science ,Absorption spectroscopy ,Physics::Instrumentation and Detectors ,Analytical chemistry ,chemistry.chemical_element ,Terbium ,Scintillator ,Ionizing radiation ,Nuclear Energy and Engineering ,chemistry ,Emission spectrum ,Irradiation ,Electrical and Electronic Engineering ,Absorption (electromagnetic radiation) ,Radiation hardening - Abstract
Radiation hardness is one of the fundamental parameters characterizing a scintillator. The reason is that ionizing radiation often induces the formation of color centers in the irradiated material. These centers are related to lattice defects and may absorb light in the visible range. Possible overlap of the induced absorption spectrum with the emission spectrum of the scintillator can reduce the number of photons emitted by the scintillator, influencing negatively the energy resolution of the detector. In this paper, the irradiation (/sup 60/Co) induced absorption of Ce/sup 3+/ (Tb/sup 3+/) phosphate scintillating glasses is reported in the dose range 1-10 Gy. Irradiation tests were performed in the "Calliope" irradiation plant, placed in the Research Centre ENEA-Casaccia in the same dosimetric point (3.7 Gy/h), and the irradiation-induced damage was investigated by transmission measurements. Results are discussed by taking into account the possible dependence of radiation hardness on the composition of glass matrix. more...
- Published
- 2002
- Full Text
- View/download PDF
335. Enhanced and shortened Mn^2+ emissions by Cu^+ co-doping in borosilicate glasses for W-LEDs
- Author
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Alessia Cemmi, Ning Yang, Cai Qiaosong, Stefania Baccaro, Guo-Rong Chen, Haiyuan Xu, Mauro Falconieri, and Fanliang Zhou
- Subjects
Valence (chemistry) ,Materials science ,Borosilicate glass ,Doping ,Analytical chemistry ,chemistry.chemical_element ,Manganese ,Copper ,Photon upconversion ,Electronic, Optical and Magnetic Materials ,Ion ,Condensed Matter::Materials Science ,Microsecond ,chemistry - Abstract
A novel pair of transition metal ions Cu+, Mn2+ is co-doped in borosilicate glasses. Both copper and manganese ions exist in lower valence states (Cu+, Mn2+) in the as-prepared glasses. Around 5-time enhanced Mn2+ emission under the UV excitation is observed, which, as demonstrated by excitation spectra and emission decay curves, is due to an energy transfer from Cu+ ions resulting in greatly increased absorption of Mn2+ ions in the UV region, and relaxation on doubly-forbidden transition of Mn2+ leading to the much shortened Mn2+ emission lifetime from millisecond to microsecond level. Besides, a composite white emission is generated by combining the blue-green part from Cu+ ions with the green-red part from Mn2+ ions and it can be effectively tuned from cold to warm by adjusting host glass composition and altering excitation wavelength. Relevant mechanisms are discussed. more...
- Published
- 2014
- Full Text
- View/download PDF
336. Broadly tunable emission from Mn-doped zinc gallogermanate phosphors through composition modification
- Author
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Chunming Chen, Nan Huang, Huidan Zeng, Liu Zhibin, Guo-Rong Chen, Jing Ren, Xiaoqing Xu, Deshuang Kong, Haizheng Tao, Linren Kong, and Changjun Gu
- Subjects
Materials science ,business.industry ,chemistry.chemical_element ,Phosphor ,Zinc ,Photochemistry ,Electronic, Optical and Magnetic Materials ,Pulsed laser deposition ,Field electron emission ,chemistry ,X-ray crystallography ,Optoelectronics ,Composition (visual arts) ,Mn doped ,business ,Luminescence - Abstract
Nowadays, one-phase and full-color phosphors have gained increasing interest. Here, we show that Mn-activated zinc gallogermanate, Zn1+xGa2-2xGexO4: Mn, x = 0 ~1, phosphors exhibit a broadly tunable luminescence from green to deep red with the substitution of Ga3+ by Ge4+. The green and deep red emissions are attributed to Mn2+ and Mn4+ occupying the tetrahedrally coordinated Zn2+ and octahedrally coordinated Ga3+ sites, respectively. The origin of the tunable luminescence is discussed. The present phosphors have potential uses in field emission displays and in vivo bio-imaging. more...
- Published
- 2014
- Full Text
- View/download PDF
337. Green synthesis of highly efficient CdSe quantum dots for quantum-dots-sensitized solar cells
- Author
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Guo-Rong Chen, Bing Gao, Shuanglong Yuan, Yunxia Yang, Mengya Zhang, Chao Shen, and Bo Zhang
- Subjects
Materials science ,business.industry ,Photovoltaic system ,Wide-bandgap semiconductor ,General Physics and Astronomy ,Nanotechnology ,Photovoltaic effect ,Electrolyte ,Full width at half maximum ,Quantum dot ,Electrode ,Optoelectronics ,Energy transformation ,business - Abstract
Green synthesis of CdSe quantum dots for application in the quantum-dots-sensitized solar cells (QDSCs) is investigated in this work. The CdSe QDs were prepared with glycerol as the solvent, with sharp emission peak, full width at half maximum around 30 nm, and absorption peak from 475 nm to 510 nm. The reaction is environmental friendly and energy saving. What's more, the green synthesized CdSe QDs are coherence to the maximum remittance region of the solar spectrum and suitable as sensitizers to assemble onto TiO2 electrodes for cell devices application. What's more, the dynamic procedure of the carriers' excitation, transportation, and recombination in the QDSCs are discussed. Because the recombination of the electrons from the conduction band of TiO2's to the electrolyte affects the efficiency of the solar cells greatly, 3-Mercaptopropionic acid capped water-dispersible QDs were used to cover the surface of TiO2. The resulting green synthesized CdSe QDSCs with Cu2S as the electrode show a photovoltaic... more...
- Published
- 2014
- Full Text
- View/download PDF
338. A Shortcut to the Preparation of Naturally Occurring Arbutin
- Author
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Guo-Rong Chen, Jia-Lu Xue, Qiong Deng, Jin-Wei Yang, and Xiao-Peng He
- Subjects
chemistry.chemical_compound ,Glycosylation ,Anomer ,Hydroquinone ,chemistry ,Carbohydrate chemistry ,Yield (chemistry) ,Final product ,Arbutin ,Microwave irradiation ,Organic chemistry ,General Chemistry - Abstract
Never-theless, although these glycosylations proceeded smoothly and afforded effectively the final product, there still remain several drawbacks such as incomplete anomeric retention, relatively low total yield and especially, long reaction time (commonly more than 24 h for 2 - 3 steps).Microwave irradiation is known as a powerful tool for both enhancing the reaction efficacy and economizing the reaction time. To our surprise, though this methodology has been ma-ssively introduced into carbohydrate chemistry more...
- Published
- 2010
- Full Text
- View/download PDF
339. Glass transition temperature and topological constraints of sodium borophosphate glass-forming liquids
- Author
-
Zhaofeng Wang, Qi Jiang, Jing Ren, Huidan Zeng, Guo-Rong Chen, Luyi Sun, Donghui Zhao, and Zhao Liu
- Subjects
Materials science ,General Physics and Astronomy ,chemistry.chemical_element ,Topology ,Network topology ,Condensed Matter::Disordered Systems and Neural Networks ,Condensed Matter::Soft Condensed Matter ,Constraint (information theory) ,Nonlinear system ,Distribution (mathematics) ,chemistry ,Vitrification ,Physical and Theoretical Chemistry ,Glass transition ,Boron ,Scaling - Abstract
Sodium borophosphate glasses exhibit intriguing mixed network former effect, with the nonlinear compositional dependence of their glass transition temperature as one of the most typical examples. In this paper, we establish the widely applicable topological constraint model of sodium borophosphate mixed network former glasses to explain the relationship between the internal structure and nonlinear changes of glass transition temperature. The application of glass topology network was discussed in detail in terms of the unified methodology for the quantitative distribution of each coordinated boron and phosphorus units and glass transition temperature dependence of atomic constraints. An accurate prediction of composition scaling of the glass transition temperature was obtained based on topological constraint model. more...
- Published
- 2013
- Full Text
- View/download PDF
340. Bright green emission from the Mn^2+-doped zinc gallogermanate phosphors
- Author
-
Xiaoqing Xu, Deshuang Kong, Jing Ren, Guo-Rong Chen, Chunming Chen, Changjun Gu, and Linren Kong
- Subjects
Materials science ,Doping ,Analytical chemistry ,chemistry.chemical_element ,Phosphor ,Zinc ,Electronic, Optical and Magnetic Materials ,law.invention ,Condensed Matter::Materials Science ,X-ray photoelectron spectroscopy ,chemistry ,law ,Condensed Matter::Superconductivity ,X-ray crystallography ,Physics::Atomic and Molecular Clusters ,Condensed Matter::Strongly Correlated Electrons ,Physics::Chemical Physics ,Luminescence ,Electron paramagnetic resonance ,Solid solution - Abstract
Bright green emission is obtained from the Mn2+-doped zinc gallogermanate phosphors. The X-ray diffraction (XRD) and photoelectron spectroscopy (XPS) confirm that zinc gallogermanate so obtained is a solid solution of ZnGa2O4 and Zn2GeO4. The slight change of structure for different sintered hours is reflected in the emission intensity of the Mn2+-doped samples. The low temperature electron paramagnetic resonance (EPR) spectra and PL decay curves are employed to probe into the different luminescence centers in the non-doped and Mn2+-doped zinc gallogermanate phosphors. more...
- Published
- 2013
- Full Text
- View/download PDF
341. Sensors: Fluorogenic Probing of Specific Recognitions between Sugar Ligands and Glycoprotein Receptors on Cancer Cells by an Economic Graphene Nanocomposite (Adv. Mater. 30/2013)
- Author
-
Qibin Chen, Hai-Lin Zhang, Xiao-Li Wei, Guo-Rong Chen, Yi-Tao Long, Jia-Yi Cao, Kaixian Chen, Shanshan Liu, Jia Li, Xiao-Peng He, and Yi Zang
- Subjects
chemistry.chemical_classification ,Nanocomposite ,Materials science ,Graphene ,Mechanical Engineering ,Nanotechnology ,law.invention ,Rhodamine ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,law ,Cancer cell ,Click chemistry ,General Materials Science ,Sugar ,Receptor ,Glycoprotein - Published
- 2013
- Full Text
- View/download PDF
342. Bis-triazolyl indoleamines as unique 'off–approach–on' chemosensors for copper and fluorine
- Author
-
Guo-Rong Chen, Yuanchao Li, Bin Zhang, Xiao-Peng He, Yaxi Yang, Kaixian Chen, Chu-Chu Guan, and De-Tai Shi
- Subjects
Indole test ,Molecular Structure ,chemistry.chemical_element ,Fluorine ,Triazoles ,Biochemistry ,Copper ,Analytical Chemistry ,chemistry ,Electrochemistry ,Environmental Chemistry ,Organic chemistry ,Colorimetry ,Fluorometry ,Amines ,Spectroscopy - Abstract
Bis-triazolyl indoleamine-based chemosensors that respond to copper, and then fluorine as presumably facilitated by the high-affinity interaction between F(-) and the NH-proton of indole, are reported. Remarkable fluorimetric as well as colorimetric alternations upon the specific ligand-ion recognitions were observed. more...
- Published
- 2013
- Full Text
- View/download PDF
343. Controllable 3D crystallization in SiO2-based glasses by femtosecond laser
- Author
-
Chaxing Fan, Huidan Zeng, Guo-Rong Chen, Bertrand Poumellec, Xiujian Zhao, Matthieu Lancry, Qiming Liu, Xuan He, and François Brisset
- Subjects
Diffraction ,Materials science ,Precipitation (chemistry) ,Scanning electron microscope ,business.industry ,Physics::Optics ,Laser ,law.invention ,Optics ,law ,Femtosecond ,Nano ,Irradiation ,Crystallization ,business - Abstract
The use of femtosecond laser (fs laser) to rationally manipulate micro-/nano-structures inside transparent materials is of great interest since it allows engineering the optical properties of the material via controlling distribution, size and spatial orientation of nano/micro-crystals in glass [1]. In present work, the direct photoinduced precipitation of crystals is taken in silica-based glasses by ultra-short laser irradiation via manipulation of applied pulse energy in 32.5Li2O-27.5Nb2O5-40SiO2 glass. And the size and orientation of these crystals are characterized by Scanning Electron Microscope-Electron Backscattered Diffraction (SEM-EBSD) method. We also discuss the mechanism of controllable crystallization in glass using femtosecond laser in this paper. more...
- Published
- 2013
- Full Text
- View/download PDF
344. Different distribution of breast ductal carcinoma in situ, ductal carcinoma in situ with microinvasion, and invasion breast cancer
- Author
-
Wei, Zhang, primary, Er-li, Gao, additional, Yi-li, Zhou, additional, Qi, Zhai, additional, Zhang-yong, Zou, additional, Gui-long, Guo, additional, Guo-rong, Chen, additional, Hua-min, Zheng, additional, Guan-li, Huang, additional, and Xiao-hua, Zhang, additional more...
- Published
- 2012
- Full Text
- View/download PDF
345. Prognostic Significance of PAX8, Survivin, and Ki-67 Expression in Pancreatic Endocrine Neoplasms: A Tissue Microarray Analysis
- Author
-
Alison L. Van Dyke, Marie E. Robert, Fang Bao, Barton Kenney, Guoping Cai, Jane Bernstein, Yunhua Bao, Manju L. Prasad, and Guo-rong Chen
- Subjects
Oncology ,medicine.medical_specialty ,Tissue microarray ,biology ,business.industry ,General Medicine ,Tissue Microarray Analysis ,Ki-67 ,Internal medicine ,Endocrine neoplasm ,Survivin ,biology.protein ,Cancer research ,Medicine ,business ,PAX8 - Published
- 2012
- Full Text
- View/download PDF
346. Intense near-infrared and midinfrared luminescence from the Dy3+-doped GeSe2–Ga2Se3–MI (M=K, Cs, Ag) chalcohalide glasses at 1.32, 1.73, and 2.67 μm
- Author
-
B. Frumarová, Miloslav Frumar, Miloslav Kincl, Guo-Rong Chen, Jiri Oswald, Tomas Wagner, Jing Ren, and M. Bartos
- Subjects
Materials science ,Photoluminescence ,business.industry ,Oscillator strength ,Doping ,Analytical chemistry ,General Physics and Astronomy ,Infrared spectroscopy ,Emission intensity ,Semiconductor laser theory ,Optics ,Luminescence ,Absorption (electromagnetic radiation) ,business - Abstract
The intense 1.32, 1.73, and 2.67 μm near-infrared and midinfrared emissions were observed from the Dy3+-doped GeSe2–Ga2Se3–MI (M=K, Cs, Ag) chalcohalide glasses. These glasses are red light transparent therefore can be pumped by a semiconductor lasers operating at ∼808 nm. The 2.67 μm emission has not been reported yet which corresponds to an absorption minimum in fluoride fibers and can be very useful for long distance communications. The intensity of emissions is very sensitive to the local chemical environment of Dy3+ ions embedded in these metal halide modified glasses. A plausible correspondence between the emission intensity and the average oscillator strength was found. more...
- Published
- 2011
- Full Text
- View/download PDF
347. Microwave-assisted construction of triazole-linked amino acid–glucoside conjugates as novel PTP1B inhibitors
- Author
-
Cheng-Jiang Zhu, Qiang Shen, Hai-Lin Zhang, Jia Li, Zhuo Song, Juan Xie, Xiao-Xin Shi, Guo-Rong Chen, Xiao-Peng He, Li Sheng, Cui Li, Yun Tang, Xiao-Ping Jin, and Wei Zhang
- Subjects
chemistry.chemical_classification ,Stereochemistry ,Triazole ,Phenylalanine ,General Chemistry ,Catalysis ,Amino acid ,chemistry.chemical_compound ,Enzyme ,chemistry ,Glucoside ,Docking (molecular) ,Materials Chemistry ,Glycosyl ,Tyrosine - Abstract
There has been increasing interest in the development of protein tyrosine phosphatase 1B (PTP1B) inhibitors for the treatment of type 2 diabetes, obesity and breast cancer. We report here the identification of a series of mono- and bis-phenylalaninyl and tyrosinyl glucoside derivatives as novel PTP1B inhibitors. The designed compounds bearing one or two phenylalanine or tyrosine derivatives on the 6-, 2,3-, 2,6-, 3,4- and 4,6-positions of the glucosyl scaffolds were efficiently constructed via the microwave-assisted Cu(I)-catalyzed azide–alkyne cycloaddition in moderate-to-excellent yields. Successive biological assays identified these compounds as novel PTP1B inhibitors, with the 4,6-disubstituted tyrosinyl glucoside being the most potent. A kinetic study established that both mono- and bis-triazole-linked glycosyl acids act as typical competitive inhibitors whereas the bis-triazolyl ester that also exhibited inhibitory activity on PTP1B displayed a mixed-type inhibition pattern. Furthermore, docking simulation plausibly proposed the diverse binding modes of these compounds with the enzymatic target. more...
- Published
- 2011
- Full Text
- View/download PDF
348. Environmentally benign metal triflate-catalyzed reductive cleavage of the C–O bond of acetals to ethers
- Author
-
Guo-Rong Chen, Marc Lemaire, Wissam Dayoub, and Yin-Jie Zhang
- Subjects
Nitrile ,Chemistry ,Aromaticity ,Pollution ,Medicinal chemistry ,Catalysis ,Metal ,chemistry.chemical_compound ,Reagent ,Atom economy ,visual_art ,Nitro ,visual_art.visual_art_medium ,Environmental Chemistry ,Organic chemistry ,Trifluoromethanesulfonate - Abstract
A protocol is described for the reductive cleavage of the C–O bond of aromatic and aliphatic acetals to ethers catalyzed by Cu(OTf)2 or Bi(OTf)3 at room temperature in excellent yields, without affecting aromatic rings, nitro, nitrile, ester and hydroxyl groups. This protocol represents an improvement in terms of atom economy compared to the previous methods, by distinctly decreasing the amount of the reducing reagent, 1,1,3,3-tetramethyldisiloxane (TMDS), and using a small amount of catalyst. more...
- Published
- 2011
- Full Text
- View/download PDF
349. Selective synthesis of 1-O-alkyl glycerol and diglycerol ethers by reductive alkylation of alcohols
- Author
-
Guo-Rong Chen, Yan Shi, Wissam Dayoub, and Marc Lemaire
- Subjects
chemistry.chemical_classification ,010405 organic chemistry ,Ether ,Alkylation ,010402 general chemistry ,01 natural sciences ,Pollution ,Aldehyde ,0104 chemical sciences ,Catalysis ,chemistry.chemical_compound ,chemistry ,Glycerol ,Environmental Chemistry ,Organic chemistry ,lipids (amino acids, peptides, and proteins) ,Brønsted–Lowry acid–base theory ,Selectivity ,Alkyl - Abstract
1-O-alkyl glycerol and diglycerol ethers are obtained in high yields and high selectivity by catalytic reductive alkylation of glycerol and diglycerol with linear aldehydes in the presence of 0.5 mol% of Pd/C under 10 bars of hydrogen using a Bronsted acid as co-catalyst. All byproducts were identified. A mechanism for the reductive alkylation is proposed. more...
- Published
- 2010
- Full Text
- View/download PDF
350. Near Infrared Broadband Emission from Bismuth–Dysprosium Codoped Chalcohalide Glasses
- Author
-
Jing, Ren, primary, Dan-Ping, Chen, additional, Guang, Yang, additional, Yin-Sheng, Xu, additional, Hui-Dan, Zeng, additional, and Guo-Rong, Chen, additional
- Published
- 2007
- Full Text
- View/download PDF
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