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Rodriguez AM, Callahan JE, Fawcett P, Ge X, Xu P, Kitten T. Physiological and molecular characterization of genetic competence in Streptococcus sanguinis. Mol Oral Microbiol 2011; 26:99-116. [PMID: 21375701 DOI: 10.1111/j.2041-1014.2011.00606.x] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Streptococcus sanguinis is a major component of the oral flora and an important cause of infective endocarditis. Although S. sanguinis is naturally competent, genome sequencing has suggested significant differences in the S. sanguinis competence system relative to those of other streptococci. An S. sanguinis mutant possessing an in-frame deletion in the comC gene, which encodes competence-stimulating peptide (CSP), was created. Addition of synthetic CSP induced competence in this strain. Gene expression in this strain was monitored by microarray analysis at multiple time-points from 2.5 to 30 min after CSP addition, and verified by quantitative reverse transcription-polymerase chain reaction. Over 200 genes were identified whose expression was altered at least two-fold in at least one time point, with the majority upregulated. The 'late' response was typical of that seen in previous studies. However, comparison of the 'early' response in S. sanguinis with that of other oral streptococci revealed unexpected differences with regard to the number of genes induced, the nature of those genes, and their putative upstream regulatory sequences. Streptococcus sanguinis possesses a comparatively limited early response, which may define a minimal streptococcal competence regulatory circuit.
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202
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Lv XJ, Lu J, Xie ZD, Yang J, Zhao G, Xu P, Qin YQ, Zhu SN. Polarization-free second-order nonlinear frequency conversion using the optical superlattice. OPTICS LETTERS 2011; 36:7-9. [PMID: 21209669 DOI: 10.1364/ol.36.000007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
We propose a universal and practical scheme to realize polarization-free second-order nonlinear frequency-conversion processes, including sum-frequency generation, difference-frequency generation, and optical parametric amplification. This scheme is based on the optical superlattice with a noncritical phase-matching condition, which is suitable for optical integration. A chirped dual-period structure is proposed to ensure the efficiency and stability of the conversions.
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203
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Zhou Y, Chen XP, Liang C, Xu P. Resistance Properties of a Bend in Dense-Phase Pneumatic Conveying of Pulverized Coal under High Pressure. Chem Eng Technol 2010. [DOI: 10.1002/ceat.201000307] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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204
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Hu J, Zuo G, Li J, Luo N, Zakharov L, Zhang L, Zhang W, Xu P. Investigation of lithium as plasma facing materials on HT-7. FUSION ENGINEERING AND DESIGN 2010. [DOI: 10.1016/j.fusengdes.2010.08.034] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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205
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Guarise M, Dalla Piazza B, Moretti Sala M, Ghiringhelli G, Braicovich L, Berger H, Hancock JN, van der Marel D, Schmitt T, Strocov VN, Ament LJP, van den Brink J, Lin PH, Xu P, Rønnow HM, Grioni M. Measurement of magnetic excitations in the two-dimensional antiferromagnetic Sr₂CuO₂Cl₂ insulator using resonant x-ray scattering: evidence for extended interactions. PHYSICAL REVIEW LETTERS 2010; 105:157006. [PMID: 21230933 DOI: 10.1103/physrevlett.105.157006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2010] [Indexed: 05/30/2023]
Abstract
We measured the momentum dependence of magnetic excitations in the model spin-1/2 2D antiferromagnetic insulator Sr2CuO2Cl2 (SCOC). We identify a single-spin-wave feature and a multimagnon continuum, with different polarization dependences. The spin waves display a large (70 meV) dispersion between the zone-boundary points (π, 0) and (π/2, π/2). Employing an extended t-t'-t''-U one-band Hubbard model, we find significant electronic hopping beyond nearest-neighbor Cu ions, indicative of extended magnetic interactions. The spectral line shape at (π, 0) indicates sizable quantum effects in SCOC and probably more generally in the cuprates.
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206
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Zhang J, Ge X, Xu P, Feng S. e0449 Effects of cholesterol-lowering therapy with rosuvastatin calcium tablet on coronary flow reserve in patients with unstable angina pectoris. BRITISH HEART JOURNAL 2010. [DOI: 10.1136/hrt.2010.208967.449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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207
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Xu P, Irby JH, Bergerson WF, Bosco J, Brower DL, Ding WX, Kanojia A, Leccacorvi R, Mansfield DK, Marmar ES, Michael P, Murray R, Rokhman Y, Vieira R. Preliminary results from the Alcator C-Mod polarimeter. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:10D507. [PMID: 21033862 DOI: 10.1063/1.3466803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
A poloidally viewing far infrared polarimeter diagnostic is being developed for the Alcator C-Mod tokamak, and will be used to determine the q-profile and to study density and magnetic field fluctuations. A three-chord version of what will eventually be up to a ten-chord system has been designed and fabricated and will be installed on C-Mod before the end of the current run period. Bench tests of a single chord mock-up of this system show acceptable noise levels for the planned measurements. We will discuss the analysis and experimental techniques used to diagnose and reduce noise sources.
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208
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Peng L, Ren LB, Dong G, Wang CL, Xu P, Ye L, Zhou XD. Wnt5a promotes differentiation of human dental papilla cells. Int Endod J 2010; 43:404-12. [PMID: 20518933 DOI: 10.1111/j.1365-2591.2010.01693.x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
AIM To investigate the role of Wnt5a in the process of differentiation of human dental papilla cells (HDPCs). METHODOLOGY Recombinant adenovirus encoding full-length Wnt5a cDNA was constructed to investigate the biological role of Wnt5a on the differentiation of HDPCs. The effect of Wnt5a on HDPCs differentiation was determined by ALP activity assay, ALP staining and mineral induction assay. Mineralization-related gene expressions were assessed by RT-PCR. RESULTS Immunostaining revealed Wnt5a expression in the odontoblast layer and dental papilla tissue. Over-expression of Wnt5a by transfecting HDPCs with an Wnt5a-carrying construct increased ALPase activity and the formation of mineralized nodules of HDPCs. RT-PCR analysis showed that the expressions of mineralization-related genes, such as bone sialoprotein, collagen type I, osteonectin, osteopontin (OCN), dentine matrix protein-1 were up-regulated by Wnt5a. CONCLUSIONS Wnt5a promoted differentiation of HDPCs.
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209
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Liu JT, Guo X, Ma WJ, Zhang YG, Xu P, Yao JF, Bai YD. Mitochondrial function is altered in articular chondrocytes of an endemic osteoarthritis, Kashin-Beck disease. Osteoarthritis Cartilage 2010; 18:1218-26. [PMID: 20650322 DOI: 10.1016/j.joca.2010.07.003] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2010] [Revised: 07/08/2010] [Accepted: 07/14/2010] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Kashin-Beck disease (KBD) is an endemic degenerative osteoarthritis (OA) associated with extracellular matrix degradation and chondrocyte necrosis in the articular and growth plate cartilage. The role of mitochondria in degenerative diseases is widely recognized but its function in KBD is unknown. The aim of this investigation was to evaluate mitochondrial function to understand the mitochondria-mediated caspase activation and apoptosis in adult KBD chondrocytes. METHODS Mitochondrial function was evaluated by analyzing the activities of respiratory chain enzyme complexes and citrate synthase (CS), intracellular adenosine triphosphate (ATP) contents, as well as changes in mitochondrial membrane potential (DeltaPsim). Apoptotic cell death was evaluated by analyzing the cytochrome c release from mitochondria to the cytosol, caspase-9 and 3 activities, and the apoptosis rate of KBD articular chondrocytes. RESULTS Activities of complexes II, III, IV and V were reduced in KBD articular chondrocytes compared with cells from normal controls. However, the mitochondrial mass was increased in KBD samples. Cultured KBD chondrocytes had a reduction of cellular ATP levels and contained a higher proportion of cells with de-energized mitochondria. Mitochondrial cytochrome c release and activation of caspase-9 and 3 were also observed. The percentages of positive apoptotic chondrocytes from the KBD patient group stained by Hoechst nuclear stain and Annexin V/PI for flow cytometry exhibited higher levels than that of the healthy controls. CONCLUSION These findings suggest the involvement of mitochondrial function and apoptotic cell death in the pathophysiology of KBD. The dysfunction of the mitochondria may play an important role in KBD articular chondrocytes apoptosis.
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210
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Yang J, Hu XP, Xu P, Lv XJ, Zhang C, Zhao G, Zhou HJ, Zhu SN. Chirped-quasi-periodic structure for quasi-phase-matching. OPTICS EXPRESS 2010; 18:14717-14723. [PMID: 20639957 DOI: 10.1364/oe.18.014717] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We propose in this paper a chirped-quasi-periodic structure using the projection method. This type of new structure combines the advantages of chirped and quasi-periodic structures, and can be used for both multiple quasi-phase-matching and multiple bandwidths control. Numerical simulation of second-harmonic generation performance is in good agreement with the Fourier spectrum of the structure.
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211
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Zhao LN, Su J, Hu XP, Lv XJ, Xie ZD, Zhao G, Xu P, Zhu SN. Single-pass sum-frequency-generation of 589-nm yellow light based on dual-wavelength Nd:YAG laser with periodically-poled LiTaO(3) crystal. OPTICS EXPRESS 2010; 18:13331-13336. [PMID: 20588462 DOI: 10.1364/oe.18.013331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We demonstrate a compact all-solid-state yellow laser source based on Q-switched dual-wavelength Nd:YAG laser and periodically-poled LiTaO(3) crystal. 589-nm yellow light was generated by single-pass sum-frequency generation of the fundamental IR waves at 1064 and 1319 nm. The maximum output power of yellow light was 506 mW and the corresponding conversion efficiency was approximately 5.5% [W(-1)cm(-1)].
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212
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Xu P, Lin SY, Hu LQ, Duan YM, Zhang JZ, Chen KY, Zhong GQ. First results obtained from the soft x-ray pulse height analyzer on experimental advanced superconducting tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2010; 81:063501. [PMID: 20590235 DOI: 10.1063/1.3443572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
An assembly of soft x-ray pulse height analyzer system, based on silicon drift detector (SDD), has been successfully established on the experimental advanced superconducting tokamak (EAST) to measure the spectrum of soft x-ray emission (E=1-20 keV). The system, including one 15-channel SDD linear array, is installed on EAST horizontal port C. The time-resolved radial profiles of electron temperature and K(alpha) intensities of metallic impurities have been obtained with a spatial resolution of around 7 cm during a single discharge. It was found that the electron temperatures derived from the system are in good agreement with the values from Thomson scattering measurements. The system can also be applied to the measurement of the long pulse discharge for EAST. The diagnostic system is introduced and some typical experimental results obtained from the system are also presented.
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213
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Wang C, Xu P, Ren L, Dong G, Ye L. Comparison of post-obturation pain experience following one-visit and two-visit root canal treatment on teeth with vital pulps: a randomized controlled trial. Int Endod J 2010; 43:692-7. [DOI: 10.1111/j.1365-2591.2010.01748.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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214
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Lu ZL, Xu P, Wang X, Dosher B, Zhou J, Zhang D, Zhou Y. Category and perceptual learning in subjects with treated wilson's disease. J Vis 2010. [DOI: 10.1167/8.6.977] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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215
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Peng L, Dong G, Xu P, Ren L, Wang C, Aragon M, Zhou X, Ye L. Expression of Wnt5a in tooth germs and the related signal transduction analysis. Arch Oral Biol 2010; 55:108-14. [DOI: 10.1016/j.archoralbio.2009.12.002] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2009] [Revised: 11/19/2009] [Accepted: 12/04/2009] [Indexed: 11/27/2022]
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216
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Bellona CL, Wuertle A, Xu P, Drewes JE. Evaluation of a bench-scale membrane fouling protocol to determine fouling propensities of membranes during full-scale water reuse applications. WATER SCIENCE AND TECHNOLOGY : A JOURNAL OF THE INTERNATIONAL ASSOCIATION ON WATER POLLUTION RESEARCH 2010; 62:1198-1204. [PMID: 20818065 DOI: 10.2166/wst.2010.416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
There is increasing interest in recycling wastewater effluents for augmentation of existing water supplies. The treatment of wastewater effluents by an integrated membrane system, such as microfiltration pre-treatment followed by reverse osmosis, is the industry standard for groundwater recharge or reservoir augmentation projects. Membrane fouling, especially effluent organic matter fouling, is a major challenge for water reuse applications employing high-pressure membranes. While fouling control through pre-treatment is an important aspect in membrane system design and operation, selecting low fouling membranes is an equally important aspect. Although recent research has begun to elucidate fouling mechanisms, little work has been performed to develop methods to pre-determine the effluent organic matter fouling propensities of high-pressure membranes so that low-fouling membranes can be pre-selected for reuse applications. The purpose of this study was to utilize a bench-scale testing protocol to test the relative effluent organic matter fouling propensities of commercially available NF and RO membranes when treating wastewater effluents. Bench-scale fouling test results were then compared to operational data generated during pilot- and full-scale membrane testing. Pilot- and full-scale testing using recycled water demonstrated that membranes foul at significantly different rates and that the extent of fouling could be estimated utilizing the proposed bench-scale testing protocol.
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217
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Xu P, Ling J, Li D, Hasegawa PM, Bressan RA. Identification of a novel DNA-binding protein to osmotin promoter. ACTA ACUST UNITED AC 2009; 41:657-63. [PMID: 18726223 DOI: 10.1007/bf02882909] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/1998] [Indexed: 11/28/2022]
Abstract
One novel osmotin promoter, binding-protein (OPBP1) gene, was isolated from salt-adapted tobacco suspension cells using yeast one-hybrid system. The OPBP1 interacted specifically in vivo with FA, a DNA sequence from the 5 upstream region of osmotin gene, which was essential for osmotin responsiveness. The deduced amino acid sequence of OPBP1 contained a conserved motif of a new gene family, AP2 family. This protein did not contain the typical motif found in the most known DNA-binding proteins and transcription factors.
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218
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Peng L, Ye L, Dong G, Ren L, Wang C, Xu P, Zhou X. WNT5A inhibits human dental papilla cell proliferation and migration. Biochem Biophys Res Commun 2009; 390:1072-8. [DOI: 10.1016/j.bbrc.2009.10.136] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2009] [Accepted: 10/23/2009] [Indexed: 10/20/2022]
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219
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Song L, Xu P, Wang H, Yang Y. Inclusion phenomena of clove oil with α-, β-, γ- and heptakis (2,6-di-O-methyl)-β-cyclodextrin. Nat Prod Res 2009; 23:789-800. [DOI: 10.1080/14786410801937105] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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220
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Le W, Xu P, Pan T, Deng H, Xie W, Jankovic J. FP41-TH-01 Nurr1 and Pitx3 are risk factors for Parkinson's disease. J Neurol Sci 2009. [DOI: 10.1016/s0022-510x(09)70484-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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221
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Abstract
AIMS To isolate and characterize bacteria capable of degrading nicotine from the rhizospheric soil of a tobacco plant and to use them to degrade the nicotine in tobacco solid waste. METHODS AND RESULTS A bacterium, strain S33, was newly isolated from the rhizospheric soil of a tobacco plant, and identified as Agrobacterium sp. based on morphology, physiological tests, Biolog MicroLog3 4.20 system and 16S rRNA gene sequence. Using nicotine as the sole source of carbon and nitrogen in the medium, it grew optimally with 1.0 g l(-1) of nicotine at 30 degrees C and pH 7.0, and nicotine was completely degraded within 6 h. The resting cells prepared from the glucose-ammonium medium or LB medium could not degrade nicotine within 10 h, while those prepared from the nicotine medium could completely degrade 3 g l(-1) of nicotine in 1.5 h at a maximal rate of 1.23 g nicotine h(-1) g(-1) dry cell. Using the medium containing nicotine, glucose and ammonium simultaneously to cultivate strain S33, the resting cells could degrade 98.87% of nicotine in tobacco solid waste with the concentration as 30 mg nicotine g(-1) dry weight tobacco solid waste within 7 h at a maximal rate of 0.46 g nicotine h(-1) g(-1) dry cell. CONCLUSIONS This is the first report that Agrobacterium sp. has the ability to degrade nicotine. Agrobacterium sp. S33 could use nicotine as the sole source of carbon and nitrogen. The use of resting cells of the strain S33 prepared from the nicotine-glucose-ammonium medium was an effective method to degrade nicotine and detoxify tobacco solid waste. SIGNIFICANCE AND IMPACT OF THE STUDY Nicotine in tobacco wastes is both toxic and harmful to human health and the environment. This study showed that Agrobacterium sp. S33 may be suitable for the disposal of tobacco wastes and reducing the nicotine content in tobacco leaves.
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222
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Huang L, Cheng T, Xu P, Duan J, Fang T, Xia Q. Immunoglobulin superfamily is conserved but evolved rapidly and is active in the silkworm, Bombyx mori. INSECT MOLECULAR BIOLOGY 2009; 18:517-530. [PMID: 19604311 DOI: 10.1111/j.1365-2583.2009.00896.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Immunoglobulin superfamily (IgSF) proteins are known for their abilities to specifically recognize and adhere to cells. In this paper, we predicted the presence of 133 IgSF proteins in the silkworm (Bombyx mori) genome. Comparison with similar proteins in other model organisms (Caenorhabditis elegans, Drosophila melanogaster, Anopheles gambiae, Apis mellifera and Homo sapiens) indicated that IgSF proteins are conserved but have rapidly evolved from worms to human beings. However, these proteins are well conserved amongst insects. Silkworm microarray-based expression data showed tissue expression of 57 IgSF genes and microbe-induced differential expression of 37 genes. Based on the expression data, we can conclude that the silkworm IgSF is active.
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223
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Xu P, Zhao LN, Lv XJ, Lu J, Yuan Y, Zhao G, Zhu SN. Compact high-power red-green-blue laser light source generation from a single lithium tantalate with cascaded domain modulation. OPTICS EXPRESS 2009; 17:9509-9514. [PMID: 19506598 DOI: 10.1364/oe.17.009509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
1W quasi-white-light source has been generated from a single lithium tantalate with cascaded domain modulation. The quasi-white-light is combined by proper proportion of the red, green and blue laser light. The red and the blue result from a compact self-sum frequency optical parametric oscillation when pumped by a single green laser. The efficiency of quasi-white-light from the green pump reaches 27%. This compact design can be employed not only as a stable and powerful RGB light source but also an effective blue laser generator.
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224
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Sheng D, Jao J, Li M, Xu P, Zhang J. RecX is Involved In the Switch between DNA Damage Response and Normal Metabolism in D. radiodurans. J Biochem 2009; 146:337-42. [DOI: 10.1093/jb/mvp072] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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225
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Feng L, Wang T, Wang Q, Xu P, Hu W. Morphology features of adult cleft lip and palate patients under Delaire cephalometric analysis. Int J Oral Maxillofac Surg 2009. [DOI: 10.1016/j.ijom.2009.03.172] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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