oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 234 )

2018 ( 2133 )

2017 ( 1990 )

2016 ( 1991 )

Custom range...

Search Results: 1 - 10 of 153020 matches for " CHEN Yu-feng "
All listed articles are free for downloading (OA Articles)
Page 1 /153020
Display every page Item
The 130 GeV gamma-ray line and Sommerfeld enhancements
Chen, Jing;Zhou, Yu-Feng
High Energy Physics - Phenomenology , 2013,
Abstract: Recently, possible indications of line spectral features in the Fermi-LAT photon spectrum towards the galactic center have been reported. If the distinct line features arise from dark matter (DM) annihilation into $\gamma X (X=\gamma, Z^{0} or h^{0})$, the corresponding annihilation cross-section is unnaturally large for typical loop-induced radiative processes. On the other hand, it is still too small to be responsible for the observed DM relic density. We show that the mechanism of Sommerfeld enhancement with scalar force-carrier can provide a simple solution to these puzzles. The possibly large Sommerfeld enhancement of the cross-section for s-wave DM annihilation can significantly reduce the required effective couplings between DM and charged particles in typical loop diagrams. The DM particles necessarily annihilate into scalar force-carriers through tree-level p-wave process, which can dominate the total DM annihilation cross-section at freeze out, resulting in the correct thermal relic density, but has subdominant contributions to the DM annihilation today due to velocity suppression. We perform detailed analysis on the effects of p-wave Sommerfeld enhancement on freeze out. The results show that with the constraints from the thermal relic density, the required effective couplings can be reduced by an order of magnitude.
Name Disambiguation Method Based on Attribute Match and Link Analysis  [PDF]
Yu-Feng Yao
Journal of Software Engineering and Applications (JSEA) , 2012, DOI: 10.4236/jsea.2012.51005
Abstract: A name disambiguation method is proposed based on attribute match and link analysis applying in the field of insurance. Aiming at the former name disambiguation methods such as text clustering method needs to be considered in a lot of useless words, a new name disambiguation method is advanced. Firstly, the same attribute matching is applied, merging the identity of a successful match, secondly, the link analysis is used, structural analysis of customers network is analyzed, Finally, the same cooperating information is merged. Experiment results show that the proposed method can realize name disambiguation successfully.
An Improved Name Disambiguation Method Based on Atom Cluster  [PDF]
Yu-Feng Yao
Communications and Network (CN) , 2012, DOI: 10.4236/cn.2012.41004
Abstract: An improved name disambiguation method based on atom cluster. Aiming at the method of character-related properties of similarity based on information extraction depends on the character information, a new name disambiguation method is proposed, and improved k-means algorism for name disambiguation is proposed in this paper. The cluster analysis cluster is introduced to the name disambiguation process. Experiment results show that the proposed method having the high implementation efficiency and can distinguish the different people with the same name.
No association between IRF3 polymorphism and susceptibility to hepatitis B virus infection in Chinese patients
Fang Yan,Yu-Feng Gao,Feng Lv,Tian-Chen Zhang
World Journal of Gastroenterology , 2012, DOI: 10.3748/wjg.v18.i4.388
Abstract: AIM: To investigate the association between three tag single nucleotide polymorphisms (tagSNPs) in interferon regulatory factors (IRF3) and the genetic susceptibility to chronic hepatitis B virus (HBV) infection. METHODS: We performed a case-control study of 985 Chinese cases of chronic HBV infection and 294 self-limiting HBV-infected individuals as controls. Three tagSNPs in IRF3 (rs10415576, rs2304204, rs2304206) were genotyped with the Multiplex SNaPshot technique. The genotype and allele frequencies were calculated and analyzed. RESULTS: The three SNPs showed no significant genotype/allele associations with chronic HBV infection. Overall allele P values were: rs10415576, P = 0.0908, odds ratio (OR) [95% confidence interval (CI)] = 1.1798 (0.9740-1.4291); rs2304204, P = 0.5959, OR (95% CI) = 1.0597 (0.8552-1.3133); rs2304206, P = 0.8372, OR (95% CI) = 1.0250 (0.8097-1.2976). Overall genotype P values were: rs10415576, P = 0.2106; rs2304204, P = 0.8458; rs2304206, P = 0.8315. There were no statistically significant differences between patients with chronic HBV infection and controls. Haplotypes generated by these three SNPs were also not significantly different between the two groups. CONCLUSION: The three tagSNPs of IRF3 are not associated with HBV infection in the Han Chinese population.
2-{[3-Methyl-4-(2,2,2-trifluoroethoxy)pyridin-2-yl]methylsulfanyl}-1H-benzimidazole monohydrate: a monoclinic polymorph
Yu-Feng Chen,Jin-Yao Chen,Ming-Huang Hong,Jie Lu
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812022131
Abstract: The title compound, C16H14F3N3OS·H2O, which had been previously characterized in the space group P-1 [Ren et al. (2011). Acta Cryst. E67, o270], has now been crystallized from 1-propanol in the monoclinic form in the space group P21/c. While the triclinic form is a Z′ = 2 crystal, the new monoclinic polymorph includes one main molecule and one water lattice molecule in the asymmetric unit. In the crystal, the water molecule is sandwiched between neighboring main molecules and behaves as both donor and acceptor in O—H...N and N—H...O hydrogen bonds with the imidazole N atoms. This pattern of chains parallel to [100] further interacts via O—H...N(pyridine) contacts.
Relationship between interleukin 18 polymorphisms and susceptibility to chronic hepatitis B virus infection
Na Li,Yu-Feng Gao,Tian-Chen Zhang,Ping Chen
World Journal of Hepatology , 2012, DOI: 10.4254/wjh.v4.i3.105
Abstract: AIM: To identify the relationship between the tagging single nucleotide polymorphism sites (tagSNPs) of the Interleukin-18 (IL-18) gene and genetic susceptibility to chronic hepatitis B virus infection in Chinese patients. METHODS: Five hundred and one cases of chronic hepatitis B virus (HBV) infection and 301 HBV natural clearance controls were studied. Two tagSNPs in the IL-18 gene (rs1946518A/C and rs574424C/G) were genotyped by the Multiplex Snapshot technique. The genotype and allele frequencies were calculated and analyzed. RESULTS: In the genotypes of rs1946518, the AA type was present at a higher frequency in the patients compared to those in the controls. Odds ratio (OR) of the AA genotype for the comparison with that of the AC and the CC genotype was 1.537 (95% confidence intervals (CI): 1.116-2.218, P = 0.009 < 0.025). In phenotypes, the allele C at rs1946518 was of a significantly lower frequency in the patients with chronic hepatitis B than that in the controls (P = 0.017 < 0.025). OR of the allele A for the comparison with that of the allele C was 1.279 (95% CI: 1.045-1.567). As for the rs574424 genotypes, no significant difference in this genotype distribution or in this allele frequency between the patients and the control subjects was observed. No significant difference in the haplotype frequencies between the patients with chronic hepatitis B and HBV natural clearance individuals was displayed. CONCLUSION: The data suggest that genotype AA and the allele A of the IL-18 at position rs1946518 are closely associated with the resistance to chronic hepatitis B and may be the dangerous gene. However, no statistical association was found between polymorphisms of rs574424 for IL-18 and hepatitis B.
The progress in methodologies to study impacts of global climate change in China
中国全球气候变化影响研究方法的进展

LI Ke-rang,CHEN Yu-feng,
李克让
,陈育峰

地理研究 , 1999,
Abstract: In this paper, the new progresses on research methodology of evaluating impacts of global Climate change in China are presented. They are experiments of laboratory, farmland field observation; methods of ice core tree-ring and historical writing; Studies of numerical models including static and dynamic model. At last, the indeterminacy and problems of existed and prospects are given.
Tris(1,10-phenanthroline-κ2N,N′)zinc(II) chloride 2-phenyl-4-selenazole-5-carboxylate decahydrate
Jin-Bei Shen,Xin Lv,Ji-Fei Chen,Yu-Feng Zhou
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811000729
Abstract: The asymmetric unit of the title salt, [Zn(C12H8N2)3](C10H6NO2Se)Cl·10H2O, contains a [Zn(phen)3]2+ cation (phen is 1,10-phenanthroline), uncoordinated chloride and 2-phenyl-4-selenazole-5-carboxylate anions and ten uncoordinated water molecules. The central ZnII ion is six-coordinated by six N atoms from three phen ligands in a distorted octahedral geometry. An extensive O—H...O, O—H...N and O—H...Cl hydrogen-bonding network stabilizes the crystal structure.
2-Phenyl-1,3-selenazole-4-carboxylic acid
Jin-Bei Shen,Xin Lv,Ji-Fei Chen,Yu-Feng Zhou
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811007185
Abstract: In the title compound, C10H7NO2Se, the two rings are twisted, making a dihedral angle of 12.42 (9)°. In the crystal, pairs of molecules are disposed about an inversion center, generating O—H...O hydrogen-bonded dimers.
Synthesis of New Zn-containing Derivative by Multi-step Ion-exchanges
CHEN Yu-Feng, ZHOU Song-Hua, YANG Xiao-Jing
无机材料学报 , 2010, DOI: 10.3724/sp.j.1077.2010.00806
Abstract: A new material, Zn-containing derivative from SrBi2Nb2O9, was synthesized by multi-step ion-exchanges with H+/(BiO)+, TMA+ (tetramethylammonium ions)/H+, and Zn(NH3)42+/TMA+ step by step. X-ray diffraction (XRD) patterns exhibite the difference in the layered structures among the precursor SrBi2Nb2O9 (SBN), its protonated product (HSN), and Zn-containing derivative (ZSN). The compositional analyses reveal the extraction of most of the bismuth atoms and the loss of a small part of the strontium atoms after protonation. The UV-Vis (ultraviolet-visible) absorption edge of the Zn-containing derivative shifts markedly to high energy compared with that of the precursor and its protonated product.
Page 1 /153020
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.