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Chen CD, King JA, Key MH, Akli KU, Beg FN, Chen H, Freeman RR, Link A, Mackinnon AJ, MacPhee AG, Patel PK, Porkolab M, Stephens RB, Van Woerkom LD. A Bremsstrahlung spectrometer using k-edge and differential filters with image plate dosimeters. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:10E305. [PMID: 19044467 DOI: 10.1063/1.2964231] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A Bremsstrahlung spectrometer using k-edge and differential filtering has been used with image plate dosimeters to measure the x-ray fluence from short-pulse laser/target interactions. An electron spectrometer in front of the Bremsstrahlung spectrometer deflects electrons from the x-ray line of sight and simultaneously measures the electron spectrum. The response functions were modeled with the Monte Carlo code INTEGRATED TIGER SERIES 3.0 and the dosimeters calibrated with radioactive sources. An electron distribution with a slope temperature of 1.3 MeV is inferred from the Bremsstrahlung spectra.
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2252
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Chen H, Shoumura S, Emura S, Bunai Y. Regional variations of vertebral trabecular bone microstructure with age and gender. Osteoporos Int 2008; 19:1473-83. [PMID: 18330606 DOI: 10.1007/s00198-008-0593-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Accepted: 02/05/2008] [Indexed: 01/18/2023]
Abstract
UNLABELLED The vertebral trabecular bone has a complex three-dimensional (3D) microstructure, with inhomogeneous morphology. A thorough understanding of regional variations in the microstructural properties is crucial for evaluating age- and gender-related bone loss of the vertebra, and may help us to gain more insight into the mechanism of the occurrence of vertebral osteoporosis and the related fracture risks. INTRODUCTION The aim of this study was to identify regional differences in 3D microstructure of vertebral trabecular bone with age and gender, using micro-computed tomography (micro-CT) and scanning electron microscopy (SEM). METHODS We used 56 fourth lumbar vertebral bodies from 28 women and men (57-98 years of age) cadaver donors. The subjects were chosen to give an even age and gender distribution. Both women and men were divided into three age groups, 62-, 77- and 92-year-old groups. Five cubic specimens were prepared from anterosuperior, anteroinferior, central, posterosuperior and posteroinferior regions at sagittal section. Bone specimens were examined by using micro-CT and SEM. RESULTS Reduced bone volume (BV/TV), trabecular number (Tb.N) and connectivity density (Conn.D), and increased structure model index (SMI) were found between ages 62 and 77 years, and between ages 77 and 92 years. As compared with women, men had higher Tb.N in the 77-year-old group and higher Conn.D in the 62- and 77-year-old groups. The central and anterosuperior regions had lower BV/TV and Conn.D than their corresponding posteroinferior region. Increased resorbing surfaces, perforated or disconnected trabeculae and microcallus formations were found with age. CONCLUSION Vertebral trabeculae are microstructurally heterogeneous. Decreases in BV/TV and Conn.D with age are similar in women and men. Significant differences between women and men are observed at some microstructural parameters. Age-related vertebral trabecular bone loss may be caused by increased activity of resorption. These findings illustrate potential mechanisms underlying vertebral fractures.
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Cheung KH, Kashyap V, Luciano JS, Chen H, Wang Y, Stephens S. Semantic mashup of biomedical data. J Biomed Inform 2008; 41:683-6. [PMID: 18703163 PMCID: PMC3742004 DOI: 10.1016/j.jbi.2008.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2008] [Revised: 07/30/2008] [Accepted: 08/05/2008] [Indexed: 12/24/2022]
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2254
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Dunn J, Magee EW, Shepherd R, Chen H, Hansen SB, Moon SJ, Brown GV, Gu MF, Beiersdorfer P, Purvis MA. High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:10E314. [PMID: 19044476 DOI: 10.1063/1.2968704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
A large radius, R=44.3 m, high resolution grating spectrometer (HRGS) with 2400 lines/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 A wavelength range. The instrument can be run with a 10-20 microm wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 A, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (full width at half maximum), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies.
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2255
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Xu X, Chen H, Fujimura T, Kawasaki S. Fine mapping of a strong QTL of field resistance against rice blast, Pikahei-1(t), from upland rice Kahei, utilizing a novel resistance evaluation system in the greenhouse. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2008; 117:997-1008. [PMID: 18758744 DOI: 10.1007/s00122-008-0839-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2008] [Accepted: 06/21/2008] [Indexed: 05/20/2023]
Abstract
Field resistances (FR) against rice blast are highly evaluated by breeders for their durability, in contrast to the conspicuous but often less durable true resistances. However, lack of efficient systems for evaluation of resistance has delayed their practical application. Kahei, an upland domestic cv., is known for its very high FR against rice blast. We fine-mapped its highest quantitative trait loci (QTL), qBFR4-1, using residual heterozygosity of recombinant inbred lines (RILs) and our semi-natural rice blast inoculation/evaluation system in the greenhouse, with comparable accuracy to the true resistance genes. This system enabled reproducible high-density infection, and consequently allowed quantification of the resistance level in individual plants. The target region was first narrowed down to about 1 Mb around at 32 Mb from the top of chromosome 4 in the Nipponbare genome, with the upland evaluation system assessing the F7 generation of Koshihikari (lowland, FR: very weak) x Kahei (upland, FR: very strong) RILs. Then, F9 plants (4,404)--siblings of hetero F8 plants at the region--were inoculated with rice blast in a greenhouse using the novel inoculation system, and individual resistance levels were diagnosed for fine QTL analysis and graphical genotyping. Thus, the resistance gene was fine-mapped within 300 kb at 31.2-31.5 Mb on chromosome 4, and designated Pikahei-1(t). By annotation analysis, seven resistance gene analog (RGA) ORFs of nucleotide-binding-site and leucine-rich-repeat (NBS-LRR)-type were found in the center of the region as the most likely candidate counterparts of the resistance gene. This is similar in structure to the recently reported Pik cluster region, suggesting that most of the other dominant QTLs of the FRs may have similar RGA structures.
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2256
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Chen H, Perchonok M. US Governmental Interagency Programs, Opportunities, and Collaboration. FOOD SCI TECHNOL INT 2008. [DOI: 10.1177/1082013208098817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Improving the quality, value, and safety of national food supplies is the common mission of several Federal agencies. Under different authorities, these agencies conduct basic and applied research, develop curriculum at higher educational institutions, and disseminate new scientific knowledge about food processing, formulation, and preservation to a broad range of stakeholders. Emerging food processing technologies, including various thermal and nonthermal processes, as well as chemical processes, have received increased attention and investment in recent years. Some agencies dealing with Emerging Technologies include the Cooperative State Research, Education, and Extension Service (CSREES), Agricultural Research Service (ARS), and Food Safety Inspection Service (FSIS), and all of the United States Department of Agriculture (USDA). The U.S. Army Natick Research Center of Department of Defense (DOD), National Aeronautics and Space Administration (NASA), and Food and Drug Administration (FDA) of Department of Human Health Service (DHHS) also are involved in this research area. These agencies have their vision, mission, strategic goals, and current programs and activities related to emerging food processing technologies. The synergy of effective collaboration and cooperation among all stakeholders is the key to generating an impact greater than the simple sum of all.
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2257
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Li M, Lan X, Chen H, Zhang L, Jing Y, Ren G, Wei T, Wang X. The novel missense mutation of goat LHX4 gene. Small Rumin Res 2008. [DOI: 10.1016/j.smallrumres.2008.06.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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2258
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Morris M, Chen H, Shiraev T. Isocaloric versus hypercaloric fat intake: Differential impact on hypothalamic NPY, POMC, glucose tolerance and adiposity in the rat. Appetite 2008. [DOI: 10.1016/j.appet.2008.04.170] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2259
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Fang HY, Cai QG, Chen H, Li QY. Effect of rainfall regime and slope on runoff in a gullied loess region on the Loess Plateau in China. ENVIRONMENTAL MANAGEMENT 2008; 42:402-411. [PMID: 18427882 DOI: 10.1007/s00267-008-9122-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2007] [Revised: 01/06/2008] [Accepted: 03/17/2008] [Indexed: 05/26/2023]
Abstract
Runoff was measured from seven plots with different slopes nested in Tuanshangou catchment on the Loess Plateau to study effect of slopes on runoff in relation to rainfall regimes. Based on nine years of field observation and K-mean clusters, 84 rainfall events were grouped into three rainfall regimes. Rainfall regime A is the group of events with strong rainfall intensity, high frequency, and short duration. Rainfall regime C consists of events with low intensity, long duration, and infrequent occurrence. Rainfall regime B is the aggregation of events of medium intensity and medium duration, and less frequent occurrence. The following results were found: (1) Different from traditional studies, runoff coefficient neither decreased nor increased, but presented peak value on the slope surfaces; (2) For individual plot, runoff coefficients induced by rainfall regime A were the highest, and those induced by rainfall regime C were the lowest; Downslope, the runoff coefficients induced by three rainfall regimes presented the same changing trend, although the peak value induced by regime A occurred on a shorter slope length compared to those by regime B and C; (3) Scale effect on runoff induced by rainfall regime A was the least, and that induced by rainfall regime C was the largest. These results can be explained by the interactions of crusting, soil moisture content, slope length and gradient, and erosion units, etc., in the context of different rainfall regimes.
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Boggula R, Lorenz F, Chen H, Gansemer C, Wertz H, Giuliacci A, Brusasco C, Mueller L, Wenz F. Commissioning of a System to Correlate Dose Measurements to Patients Anatomy. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.354] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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2261
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Jaboin J, Perez C, Chen H, Wills M, Lu B. MMP7 Gene Polymorphism Associated with Increased Local Recurrence Risk in Patients Receiving Radical Prostatectomy for Early-stage Prostate Cancer: Implications for Postoperative Radiation Therapy. Int J Radiat Oncol Biol Phys 2008. [DOI: 10.1016/j.ijrobp.2008.06.443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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2262
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Zhai W, Chen H, Yan H, Yan C, Wang G, Zhu L. Analysis and location of a rice BAC clone containing telomeric DNA sequences. SCIENCE IN CHINA. SERIES C, LIFE SCIENCES 2008; 42:68-73. [PMID: 18726500 DOI: 10.1007/bf02881750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/1998] [Indexed: 10/22/2022]
Abstract
BAC2, a rice BAC clone containing (TTTAGGG)(n) homologous sequences, was analyzed by Southern hybridization and DNA sequencing of its subclones. It was disclosed that there were many tandem repeated satellite DNA sequences, called TA352, as well as simple tandem repeats consisting of TTTAGGG or its variant within the BAC2 insert. A 0. 8 kb (TTTAGGG)(n)-containing fragment in BAC2 was mapped in the telomere regions of at least 5 pairs of rice chromosomes by using fluorescencein situ hybridization (FISH). By RFLP analysis of low copy sequences the BAC2 clone was localized in one terminal region of chromosome 6. All the results strongly suggest that the telomeric DNA sequences of rice are TTTAGGG or its variant, and the linked satellite DNA TA352 sequences belong to telomere-associated sequences.
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2263
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Huang XJ, Liu DH, Liu KY, Xu LP, Chen H, Han W, Chen YH, Wang JZ, Gao ZY, Zhang YC, Jiang Q, Shi HX, Lu DP. Erratum: Haploidentical hematopoietic stem cell transplantation without in vitro T-cell depletion for the treatment of hematological malignancies. Bone Marrow Transplant 2008. [DOI: 10.1038/bmt.2008.216] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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2264
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Liu RH, Wu G, Wu T, Fang DF, Chen H, Li SY, Liu K, Xie YL, Wang XF, Yang RL, Ding L, He C, Feng DL, Chen XH. Anomalous transport properties and phase diagram of the FeAs-based SmFeAsO1-xFx superconductors. PHYSICAL REVIEW LETTERS 2008; 101:087001. [PMID: 18764649 DOI: 10.1103/physrevlett.101.087001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2008] [Indexed: 05/26/2023]
Abstract
We report the detailed phase diagram and anomalous transport properties of Fe-based high-T_{c} superconductors SmFeAsO1-xFx. It is found that superconductivity emerges at x approximately 0.07, and optimal doping takes place in the x approximately 0.20 sample with the highest T_{c} approximately 54 K. T_{c} increases monotonically with doping; the anomaly in resistivity from structural phase or spin-density-wave order is rapidly suppressed, suggesting a quantum critical point around x approximately 0.14. As manifestations, a linear temperature dependence of the resistivity shows up at high temperatures in the x<0.14 regime but at low temperatures just above T_{c} in the x>0.14 regime; a drop in carrier density evidenced by a pronounced rise in the Hall coefficient is observed below the temperature of the anomaly peak in resistivity. A scaling behavior is observed between the Hall angle and temperature: cottheta_{H} proportional, variantT;{1.5} for all samples with different x in SmFeAsO1-xFx system.
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2265
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Zink T, Deng Z, Chen H, Yu L, Liu FT, Liu GY. High-resolution three-dimensional imaging of the rich membrane structures of bone marrow-derived mast cells. Ultramicroscopy 2008; 109:22-31. [PMID: 18790570 DOI: 10.1016/j.ultramic.2008.07.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2007] [Revised: 05/01/2008] [Accepted: 07/23/2008] [Indexed: 10/21/2022]
Abstract
Atomic force microscopy (AFM) enables high-resolution three-dimensional (3D) imaging of cultured bone marrow-derived mast cells. Cells were immobilized by a quick centrifugation and fixation to preserve their transient cellular morphologies followed by AFM characterization in buffer. This "fix-and-look" approach preserves the structural integrity of individual cells. Well-known membrane morphologies, such as ridges and microvilli, are visualized, consistent with prior electron microscopy observations. Additional information including the 3D measurements of these characteristic features are attained from AFM topographs. Filopodia and lamellopodia, associated with cell spreading, were captured and visualized in three dimensions. New morphologies are also revealed, such as high-density ridges and micro-craters. This investigation demonstrates that the "fix-and-look" approach followed by AFM imaging provides an effective means to characterize the membrane structure of hydrated cells with high resolution. The quantitative imaging and measurements pave the way for systematic correlation of membrane structural features with the biological status of individual cells.
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2266
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Pan F, Tang X, Zhang K, Li X, Xu J, Chen H, Ye DQ. Genetic susceptibility and haplotype analysis between Fcγ receptor IIB and IIIA gene with systemic lupus erythematosus in Chinese population. Lupus 2008; 17:733-8. [PMID: 18625651 DOI: 10.1177/0961203308089407] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The objective of this study is to understand the role of FcγRIIB and FcγRIIIA gene in susceptibility to systemic lupus erythematosus (SLE), and to examine possible susceptible haplotypes between two genes. A total of 119 patients with SLE from 95 nuclear families, aged from 14 to 78 years, were selected according to 1997 criteria of American College of Rheumatology. In addition, 316 family members of these patients were also genotyped. A family-based association study was used to explore the relationship between gene polymorphism and SLE. We studied 13 single-nucleotide polymorphisms (SNPs) encoding non-synonymous substitution in the FcγRIIB and FcγRIIIA gene (four SNPs in the FcγRIIB gene and nine SNPs in the FcγRIIIA gene) with respect to genetic susceptibility to SLE. All SNPs were genotyped by restriction fragment length polymorphism method. Among 13 SNPs, univariate (single-marker) family-based association tests showed that variant alleles at only four SNPs (rs10917661 and rs1050501, in exon 2 and exon 5 of FcγRIIB gene, rs403016 and rs428888, in exon3 of FcγRIIIA gene respectively) were significantly associated with genetic susceptibility to SLE. Furthermore, the haplotype-specific FBATs showed 50Ter-225Thr (34.1%, in FcγRIIB gene) and 72Arg-118Asn (40%, in the FcγRIIIA gene) haplotype were more frequently transmitted in SLE than other haplotypes ( Z = 3.539, P = 0.00042; Z = 2.678, P = 0.007412 respectively). But haplotypes were not found between FcγRIIB and FcγRIIIA gene Our results suggest that there were meaningful haplotype in FcγRIIIA and FcγRIIB gene respectively. FcγRIIIA and FcγRIIB genes in the pathogenesis of SLE may play an independent role in Chinese population.
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2267
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Zhao M, Chen H, Wang X, Yu H, Wang M, Wang J, Lan XY, Zhang CF, Zhang LZ, Guo YK, Zhang B, Hu SR. aPCR-SSCP and DNA sequencing detecting two silent SNPs at KAP8.1 gene in the cashmere goat. Mol Biol Rep 2008; 36:1387-91. [PMID: 18670906 DOI: 10.1007/s11033-008-9325-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2008] [Accepted: 07/14/2008] [Indexed: 12/01/2022]
Abstract
Keratin-associated proteins 8.1 gene (KAP8.1) is a structural gene responsible for the cashmere. KAP8.1 protein contains high glycine and tyrosine, which concerns regulation and function of the matrix structure fiber. In this study, the polymorphism of KAP8.1 gene was detected by methods of aPCR-SSCP (asymmetric polymerase chain reaction single-strand conformation polymorphism) and DNA sequencing in 791 individuals from two breeds. The results showed that there were two mutations in this gene. The mutations were described as c.63 T>G and c.66 C>G, which would result in two synonymous mutations in KAP8.1 protein. The findings go against previous research, in which there was not polymorphism at KAP8.1 gene. The reasons might be that different cashmere breeds were detected in two studies. Further analysis of results leads us to believe that the polymorphism of KAP8.1 gene might be relevant to fiber diameter.
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2268
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Lan XY, Shu JH, Chen H, Pan CY, Lei CZ, Wang X, Liu SQ, Zhang YB. A PstI polymorphism at 3'UTR of goat POU1F1 gene and its effect on cashmere production. Mol Biol Rep 2008; 36:1371-4. [PMID: 18654839 DOI: 10.1007/s11033-008-9322-4] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2008] [Accepted: 07/14/2008] [Indexed: 11/30/2022]
Abstract
POU1F1 is a positive regulator for prolactin (PRL) whose metabolites may directly or indirectly affect some aspects of the hair growth cycle, therefore, POU1F1 gene is an important candidate gene for cashmere traits selection through marker-assisted selection (MAS). Hence, in this study, the PCR-RFLP method was applied to detect a T>C transition determining a PstI polymorphism at the 3'UTR of POU1F1 locus and evaluate its associations with cashmere traits in 847 Inner Mongolia White Cashmere goats. In the analyzed population, the allelic frequencies for the T and C alleles are 0.959 and 0.041, respectively and the genotypic frequencies are in Hardy-Weinberg equilibrium (P > 0.05). Moreover, significant statistical relationships between the PstI polymorphism of POU1F1 gene and goat cashmere yields were found (*P < 0.05). When compared with TC genotype, TT genotype was associated with superior cashmere yields in 2, 4, and 5 years old individuals, as well as with average cashmere yield. Hence, TT genotype is suggested to be a molecular marker for senior cashmere yield.
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Palmer L, Lonjou C, Barnes K, Chen H, Cookson W, Deichmann K, Holloway J, Laitinen T, Wjst M, Morton N. A retrospective collaboration on chromosome 5 by the International Consortium on Asthma Genetics (COAG). Clin Exp Allergy 2008. [DOI: 10.1111/j.1365-2222.2001.01040.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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2270
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Liang YY, Zhou YX, Chen H, Note R, Mizuseki H, Kawazoe Y. Current through single conjugated molecules: calculations versus measurements. J Chem Phys 2008; 129:024901. [PMID: 18624557 DOI: 10.1063/1.2951986] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We use density functional theory based nonequilibrium Green's function to calculate the current through the different rodlike molecules at the finite temperatures self-consistently, which was compared to the experimental measurements presented by Reichert et al. [Phys. Rev. Lett. 88, 176804 (2002)] and by Mayor et al. [Angew. Chem. Int. Ed. 42, 5834 (2003)], respectively. Our results agree with the measurements very well, especially for the bias around +/-1.0 V. The investigation of the topological effect for the symmetrical molecule reveals the fact that the para position compound provides a considerably larger conductance than the meta one.
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2271
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Chang S, Deschesne K, Chen H, Weeks K, Sibata C, Carey E, Levinson L, Potter L. SU-GG-T-88: A Multi-Institutional Retrospective Study On Clinical IMRT Treatment Delivery Efficiency. Med Phys 2008. [DOI: 10.1118/1.2961840] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
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2272
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Dyer GM, Bernstein AC, Cho BI, Osterholz J, Grigsby W, Dalton A, Shepherd R, Ping Y, Chen H, Widmann K, Ditmire T. Equation-of-state measurement of dense plasmas heated with fast protons. PHYSICAL REVIEW LETTERS 2008; 101:015002. [PMID: 18764119 DOI: 10.1103/physrevlett.101.015002] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2007] [Indexed: 05/26/2023]
Abstract
Using an ultrafast pulse of mega-electron-volt energy protons accelerated from a laser-irradiated foil, we have heated solid density aluminum plasmas to temperatures in excess of 15 eV. By measuring the temperature and the expansion rate of the heated Al plasma simultaneously and with picosecond time resolution we have found the predictions of the SESAME Livermore equation-of-state (LEOS) tables to be accurate to within 18%, in this dense plasma regime, where there have been few previous experimental measurements.
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Chen H, Rygiewicz PT, Johnson MG, Harmon ME, Tian H, Tang JW. Chemistry and long-term decomposition of roots of Douglas-fir grown under elevated atmospheric carbon dioxide and warming conditions. JOURNAL OF ENVIRONMENTAL QUALITY 2008; 37:1327-1336. [PMID: 18574162 DOI: 10.2134/jeq2007.0266] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Elevated atmospheric CO(2) concentrations and warming may affect the quality of litters of forest plants and their subsequent decomposition in ecosystems, thereby potentially affecting the global carbon cycle. However, few data on root tissues are available to test this feedback to the atmosphere. In this study, we used fine (diameter < or = 2 mm) and small (2-10 mm) roots of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) seedlings that were grown for 4 yr in a 2 x 2 factorial experiment: ambient or elevated (+ 180 ppm) atmospheric CO(2) concentrations, and ambient or elevated (+3.8 degrees C) atmospheric temperature. Exposure to elevated CO(2) significantly increased water-soluble extractives concentration (%WSE), but had little effect on the concentration of N, cellulose, and lignin of roots. Elevated temperature had no effect on substrate quality except for increasing %WSE and decreasing the %lignin content of fine roots. No significant interaction was found between CO(2) and temperature treatments on substrate quality, except for %WSE of the fine roots. Short-term (< or = 9 mo) root decomposition in the field indicated that the roots from the ambient CO(2) and ambient temperature treatment had the slowest rate. However, over a longer period of incubation (9-36 mo) the influence of initial substrate quality on root decomposition diminished. Instead, the location of the field incubation sites exhibited significant control on decomposition. Roots at the warmer, low elevation site decomposed significantly faster than the ones at the cooler, high elevation site. This study indicates that short-term decomposition and long-term responses are not similar. It also suggests that increasing atmospheric CO(2) had little effect on the carbon storage of Douglas-fir old-growth forests of the Pacific Northwest.
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2274
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Liu C, Hu W, Chen H, Tang Z, Zeng C, Liu Z, Li L. Clinical and pathological study of Kimura's disease with renal involvement. J Nephrol 2008; 21:517-525. [PMID: 18651541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
OBJECTIVE Our objective was to retrospectively analyze the clinical and histological features of 8 Chinese patients with Kimura's disease and renal involvement. METHODS Eight male patients with Kimura's disease admitted to Jinling Hospital from 1998 to 2006 were included. The diagnoses were confirmed by lymphoid biopsy. Peripheral blood eosinophil, CD4+ and CD8+ T lymphoid cell count and total serum IgE level were examined. Renal biopsy, IL-4 expression cells and IgE-positive cell counts in renal tissue were performed. Follow-up data were recorded in detail. RESULTS Six patients were observed with the onset symptoms of subcutaneous mass or enlarged lymph nodes, and the other 2 with edema. Constitutional symptoms included bronchial asthma, enteritis, eczema, neuritis and nephrotic syndrome. Renal biopsy revealed mesangial proliferation with or without IgA deposition under immunofluorescence (n=6) and membranous nephropathy (n=2). Tubulointerstitial infiltration of eosinophils was found in 6 patients. IL-4-positive cells in renal interstitium were detected in 5 cases. IgE-positive cells were negative in all cases. Fusion of the epithelial foot process was observed under electron microscopy in patients with mesangial proliferation. All patients were sensitive to treatment with systemic prednisone, but 4 patients had a renal or extrarenal relapse after the dose tapered. Three patients who presented with solitary masses and underwent lymphoidectomy or mass excision were free from renal and extrarenal relapse. All patients had normal renal function at last follow-up. CONCLUSIONS Mesangial proliferation, eosinophilic infiltration and podocyte confusion are prominent histological features of this cohort of patients. Patients are sensitive to prednisone therapy but apt to relapse. Lymphoidectomy can be helpful to prevent relapse.
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Chen J, Chen H, Sanders KM, Perrino BA. Regulation of SRF/CArG-dependent gene transcription during chronic partial obstruction of murine small intestine. Neurogastroenterol Motil 2008; 20:829-42. [PMID: 18557893 PMCID: PMC8320440 DOI: 10.1111/j.1365-2982.2008.01149.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Intestinal obstructions lead to a variety of motility disorders. Small intestine smooth muscles undergo dramatic phenotypic changes in response to obstruction, but the underlying molecular mechanisms are unknown. Using RT-PCR, ChIP, Re-ChIP, and Western blots, we examined the effect of small bowel mechanical obstruction on smooth muscle gene expression. Obstruction caused a transient hyperplasia, followed by a prolonged hypertrophic response of small intestine smooth muscle cells. Smooth muscle myosin heavy chain (MHC), alpha-actin, and gamma-actin expression decreased initially, and then increased as hypertrophy developed. Myocardin expression decreased initially and then increased, while kruppel-like factors (KLF)4 and KLF5 expression increased initially, and then decreased. Serum response factor (SRF) expression decreased initially, and then recovered to sham-operated levels as hypertrophy developed. SRF binding to smooth muscle MHC and alpha-actin promoters decreased initially, but then increased above sham-operated levels as hypertrophy developed. Elk-1 binding to smooth muscle myosin heavy chain and alpha-actin promoters increased initially, and then decreased to sham-operated levels as hypertrophy developed. c-fos expression increased initially, which was associated with increased SRF/Elk-1 binding to the c-fos promoter. The Elk-1 phosphorylation inhibitor U-0126 inhibited the increase in c-fos expression. These findings indicate a dynamic response of small intestine smooth muscles to bowel obstruction involving switching between differentiated, proliferative, and hypertrophic phenotypes. These results suggest that changes in the expression and interactions between SRF, myocardin, Elk-1, and c-fos play key roles in the phenotypic switching of small intestine smooth muscles in response to mechanical obstruction.
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