39,783 research outputs found
Heterogeneous and tissue-specific regulation of effector T cell responses by IFN-gamma during Plasmodium berghei ANKA infection.
Full text linkIFN-γ and T cells are both required for the development of experimental cerebral malaria during Plasmodium berghei ANKA infection. Surprisingly, however, the role of IFN-γ in shaping the effector CD4(+) and CD8(+) T cell response during this infection has not been examined in detail. To address this, we have compared the effector T cell responses in wild-type and IFN-γ(-/-) mice during P. berghei ANKA infection. The expansion of splenic CD4(+) and CD8(+) T cells during P. berghei ANKA infection was unaffected by the absence of IFN-γ, but the contraction phase of the T cell response was significantly attenuated. Splenic T cell activation and effector function were essentially normal in IFN-γ(-/-) mice; however, the migration to, and accumulation of, effector CD4(+) and CD8(+) T cells in the lung, liver, and brain was altered in IFN-γ(-/-) mice. Interestingly, activation and accumulation of T cells in various nonlymphoid organs was differently affected by lack of IFN-γ, suggesting that IFN-γ influences T cell effector function to varying levels in different anatomical locations. Importantly, control of splenic T cell numbers during P. berghei ANKA infection depended on active IFN-γ-dependent environmental signals--leading to T cell apoptosis--rather than upon intrinsic alterations in T cell programming. To our knowledge, this is the first study to fully investigate the role of IFN-γ in modulating T cell function during P. berghei ANKA infection and reveals that IFN-γ is required for efficient contraction of the pool of activated T cells
Wave turbulence of a rotating array of quantized vortices in the T → 0 temperature limit
No full textThe dynamics of quantized vortices in the zero temperature limit is currently of great interest, particularly in the case of the Fermi superfluid He-B. Here we study wave turbulence, generated by the librating motion of a rotating cylindrical container filled with He-B, in the limit of vanishing viscous forces at temperatures . The polarization of the quantized vortices with respect to the axis of rotation is measured using non-invasive NMR techniques. We observe a decrease of the polarization when the librating motion is started, and a two-stage relaxation process when the modulation of the rotation velocity is stopped. The first relaxation process is associated with the dissipation of large-scale flow stored in inertial waves and the solid body rotation of the vortex array. From the decay of these energy reservoirs we determine the rate of energy dissipation of large-scale flow. The later second process is related to the relaxation of Kelvin waves on individual vortices. This process is monitored by the recovery of the polarization. The existence of a Kelvin wave cascade at the lowest temperatures is currently a central open question. We supply some evidence for the cascade
E-book : Industrial Transformation In The Developing World (author: Michael T. Rock & David P. Angel)
Full text linkArsip Kuliah Online 2010: E-book : Industrial Transformation In The Developing World (author: Michael T. Rock & David P. Angel
Letter from Carl Hayden to P. J Moran
No full textLetter from Carl T. Hayden to P. J. Moran concerning the alignment of the road to Bright Angel Trail
E-book : "industrial Transformations In The Developing World (author: Michael T. Rock & David. P Angel)
Full text linkArsip Kuliah Online 2010: E-book : "industrial Transformations In The Developing World (author: Michael T. Rock & David. P Angel
Letter from P. J. Moran to Carl Hayden
No full textLetter from P. J. Moran to Carl T. Hayden inquiring when construction will begin on the approach road to Bright Angel Trai
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
Full text linkThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
Letter from P. J. Moran to Carl Hayden
No full textLetter from P. J. Moran to Carl T. Hayden inquiring when construction will begin on the approach road to Bright Angel Trail
Deformation density studies of ring systems. 2. The deformation density of the diazirine ring in the X-ray structure of 3-[(p-Nitrophenoxy) methyl]-3-chlorodiazirine
No full textThe crystal structure and electron density of 3-[(p-nitrophenoxy)methyl]-3-chlorodiazirine have been analyzed using single crystal X-ray diffraction at 208 K with Mo K alpha radiation to a resolution of sin(theta(max))/lambda = 1.126 Angstrom(-1). A total of 10 440 measured reflections gave 7742 unique reflections with R(m) = 0.026. A multipole atomic density model was fitted to these reflections to give an R(F) = 0.0311. The deformation density of the phenyl portion of the compound is as expected. The dynamic deformation density of the diazirine ring, however, suggests that the bonding in the three-membered ring is a combination of the classical severely-strained cr bonding system with a significant contribution of a a donation from the N=N to an sp(2) carbon. This observation is placed in the context of similar proposals for the bonding in cyclopropanes.PT: J; CR: ALLEN FH, 1987, J CHEM SOC PERK T 2, S1 BAERT F, 1982, ACTA CRYSTALLOGR A, V38, P143 BATTAGLIA R, 1980, Z NATURFORSCH B, V35, P719 BLESSING R, ACA T, P26 CAMERON TS, 1992, J AM CHEM SOC, V114, P1889 CAMERON TS, 1994, J AM CHEM SOC, V116, P1211 CREMER D, 1985, J AM CHEM SOC, V107, P3800 CREMER D, 1985, J AM CHEM SOC, V107, P3811 DEWAR MJS, 1979, J AM CHEM SOC, V101, P783 DOMENICANO A, 1975, ACTA CRYSTALLOGR B, V31, P221 DUNITZ JD, 1983, HELV CHIM ACTA, V66, P123 HANSEN NK, 1978, ACTA CRYSTALLOGR A, V34, P909 HIRSHFELD FL, 1991, CRYST REV, V2, P169 LINDEN A, 1988, J ORG CHEM, V53, P1085 LIU MTH, 1986, J CHEM SOC PERK T 2, P211 SCHMIDT MW, 1990, QCPE B, V10, P52 SEILER P, 1988, HELV CHIM ACTA, V71, P2100 SMITH VH, 1977, ISRAEL J CHEM, V16, P87 SOUHASSOU M, 1992, J AM CHEM SOC, V114, P2371 STEINER T, 1993, ACTA CRYSTALLOGR A, V49, P379 STEVENS IDR, 1990, J CHEM SOC P2, P661 STEWART RF, 1969, J CHEM PHYS, V51, P4569 WALSH AD, 1949, T FARADAY SOC, V45, P179 WIBERG KB, 1987, J AM CHEM SOC, V109, P985; NR: 24; TC: 4; J9: J AMER CHEM SOC; PG: 7; GA: NV421Source type: Electronic(1
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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