bluuebunny/crossref_metadata_2025_split huggingface dataset:
Interaction between a 54-Kilodalton Mammalian Cell Surface Protein and Cowpea Mosaic Virus
Authors: Koudelka Kristopher J. , Rae Chris S. , Gonzalez Maria J. , Manchester Marianne 
Published: November 2006

ABSTRACT
Cowpea mosaic virus (CPMV), a plant virus that is a member of the picornavirus superfamily, is increasingly being used for nanotechnology applications, including material science, vascular imaging, vaccine development, and targeted drug delivery. For these applications, it is critical to understand the in vivo interactions of CPMV within the mammalian system. Although the bioavailability of CPMV in the mouse has been demonstrated, the specific interactions between CPMV and mammalian cells need to be characterized further. Here we demonstrate that although the host range for replication of CPMV is confined to plants, mammalian cells nevertheless bind and internalize CPMV in significant amounts. This binding is mediated by a conserved 54-kDa protein found on the plasma membranes of both human and murine cell lines. Studies using a deficient cell line, deglycosidases, and glycosylation inhibitors showed that the CPMV binding protein (CPMV-BP) is not glycosylated. A possible 47-kDa isoform of the CPMV-BP was also detected in the organelle and nuclear subcellular fraction prepared from murine fibroblasts. Further characterization of CPMV-BP is important to understand how CPMV is trafficked through the mammalian system and may shed light on how picornaviruses may have evolved between plant and animal hosts.
Proteasome-Independent Major Histocompatibility Complex Class I Cross-Presentation Mediated by Papaya Mosaic Virus-Like Particles Leads to Expansion of Specific Human T Cells
Authors: Leclerc Denis , Beauseigle Diane , Denis Jérome , Morin Hélène , Paré Christine , Lamarre Alain , Lapointe Réjean 
Published: November 2006

ABSTRACT

The development of versatile vaccine platforms is a priority that is recognized by health authorities worldwide; such platforms should induce both arms of the immune system, the humoral and cytotoxic-T-lymphocyte responses. In this study, we have established that a vaccine platform based on the coat protein of papaya mosaic virus (PapMV CP), previously shown to induce a humoral response, can induce major histocompatibility complex (MHC) class I cross-presentation of HLA-A*0201 epitopes from gp100, a melanoma antigen, and from influenza virus M1 matrix protein. PapMV proteins were able to assemble into stable virus-like particles (VLPs) in a crystalline and repetitive structure. When we pulsed HLA-A*0201
+
antigen-presenting cells (APCs) with the recombinant PapMV FLU or gp100, we noted that antigen-specific CD8
+
T cells were highly reactive to these APCs, demonstrating that the epitope from the VLPs were processed and loaded on the MHC class I complex. APCs were preincubated with two different proteasome inhibitors, which did not affect the efficiency of peptide presentation on MHC class I. Classical presentation from an endogenous antigen was abolished in the same conditions. Clearly, antigen presentation mediated by the PapMV system was proteasome independent. Finally, PapMV-pulsed APCs had the capacity to expand highly avid antigen-specific T cells against the influenza virus M1 HLA-A*0201 epitope when cocultured with autologous peripheral blood mononuclear cells. This study demonstrates the potential of PapMV for MHC class I cross-presentation and for the expansion of human antigen-specific T cells. It makes VLPs from PapMV CP a very attractive platform to trigger cellular responses for vaccine development against chronic infectious diseases and cancers.
IκB Kinase Subunits α and γ Are Required for Activation of NF-κB and Induction of Apoptosis by Mammalian Reovirus
Authors: Hansberger Mark W. , Campbell Jacquelyn A. , Danthi Pranav , Arrate Pia , Pennington Kevin N. , Marcu Kenneth B. , Ballard Dean W. , Dermody Terence S. 
Published: November 2006

ABSTRACTReoviruses induce apoptosis both in cultured cells and in vivo. Apoptosis plays a major role in the pathogenesis of reovirus encephalitis and myocarditis in infected mice. Reovirus-induced apoptosis is dependent on the activation of transcription factor NF-κB and downstream cellular genes. To better understand the mechanism of NF-κB activation by reovirus, NF-κB signaling intermediates under reovirus control were investigated at the level of Rel, IκB, and IκB kinase (IKK) proteins. We found that reovirus infection leads initially to nuclear translocation of p50 and RelA, followed by delayed mobilization of c-Rel and p52. This biphasic pattern of Rel protein activation is associated with the degradation of the NF-κB inhibitor IκBα but not the structurally related inhibitors IκBβ or IκBε. Using IKK subunit-specific small interfering RNAs and cells deficient in individual IKK subunits, we demonstrate that IKKα but not IKKβ is required for reovirus-induced NF-κB activation and apoptosis. Despite the preferential usage of IKKα, both NF-κB activation and apoptosis were attenuated in cells lacking IKKγ/Nemo, an essential regulatory subunit of IKKβ. Moreover, deletion of the gene encoding NF-κB-inducing kinase, which is known to modulate IKKα function, had no inhibitory effect on either response in reovirus-infected cells. Collectively, these findings indicate a novel pathway of NF-κB/Rel activation involving IKKα and IKKγ/Nemo, which together mediate the expression of downstream proapoptotic genes in reovirus-infected cells.
Vortex wakes of birds: recent developments using digital particle image velocimetry in a wind tunnel
Authors: Hedenström  , van Griethuijsen  , Rosén  , Spedding  
Published: November 2006

Abstract
A flying animal generates a trail of wake vortices that contain information about the time history and magnitude of aerodynamic forces developed on the wings and body. Methods for visualising and recording wake vortices have been developed, allowing quantitative measurements by digital particle image velocimetry (DPIV). Results from DPIV experiments in a wind tunnel are presented for four passerine species of differing size and morphology. The normalised vorticity and its integrated quantity, circulation (Γ) both decline gradually with increasing flight speed. The measured circulations are successfully explained by a simple aerodynamic model where a normalised circulation, Γ/Uc, represents half the time-averaged lift coefficient, which is >2 at 4 m s−1 for a thrush nightingale.
Negotiation with Terrorists
Authors: Pruitt Dean 
Published: November 2006

AbstractNegotiation with non-ideological ethno-nationalist terrorists is more common and more successful than with other kinds of terrorists. Additional strategies for dealing with terrorists include combating, isolating, and mainstreaming. There are many arguments against negotiation with terrorists, but most of them do not apply to secret backchannel talks, which are usually the method of choice in first approaching these groups. The success of negotiation depends on the development of flexibility by both the terrorists and the authorities. These and other points are illustrated with case materials from the Northern Ireland peace process, and the analysis is extended, on a speculative basis, to negotiation with several Islamic terrorist groups.
Illite-smectite diagenesis and palaeotemperatures in Northern North Sea Quaternary to Mesozoic shale sequences
Authors: Pearson M. J. , Small J. S. 
Published: November 2006

AbstractClay mineral abundances and illite-smectite (I/S) compositions have been determined by X-ray diffraction (XRD) in shales of Permo-Triassic to Quaternary age from seven wells in the Viking Graben and Moray Firth. Chemical analyses of size fractions provide evidence that diagenetic illitization of smectite has occurred during burial by uptake of Al and K, and release of Si. K-feldspar was probably the main source of K for illitization. The depth at which random I/S disappears occurs at similar temperatures (mean 93°C) in each well for which reliable measurements are available. Vitrinite reflectance measurements at this depth are also similar (mean 0·64% R0) and correspond to early oil generation. I/S diagenetic levels may have been imprinted by a Tertiary heating event.
The influence of crystallinity on magnetic ordering in natural ferrihydrites
Authors: Murad E. , Bowen L. H. , Long G. J. , Quin T. G. 
Published: November 2006

AbstractMössbauer spectra of three natural ferrihydrites of different crystallinities were collected between 295 and 4·2 K. Optimal fits of the room-temperature spectra were obtained using distributions of quadrupole-split doublets; half-widths of the distributions (0·71–0·86 mm/s) increased, and maxima (at 0·62–0·78 mm/s) shifted to higher quadrupole splittings with decreasing crystallinity. Rather poorly-defined magnetically-ordered spectral components appeared and gradually replaced the superparamagnetic doublets as temperatures were reduced. Blocking temperatures between 115 and 28 K, derived from the relative areas under the doublets and magnetic sextets, indicated average particle sizes between ∼ 5 and 3 nm. The sextets were relatively broad and could be fitted with distributions of hyperfine fields. These distributions narrowed and their maxima shifted to higher fields as temperatures decreased; the influence of superparamagnetism was no longer apparent at 4·2 K.
Improving soil clay minerals studies by high-gradient magnetic separation
Authors: Righi D. , Jadault P. 
Published: November 2006

AbstractHigh-gradient magnetic separation (HGMS) performed on the clay fraction (< 1 µm) of acid soils facilitates the separation and concentration of mineral fractions according to their Fe and Mg contents. As a result, smectitic layers formed by weathering of a chlorite were identified although they were not detected in the bulk sample. The concentration in the non-magnetic fraction of minerals with an intergrade vermiculite-chlorite behaviour enabled more accurate information to be obtained on these minerals.
The Hinckley index for kaolinites
Authors: Plançon A. , Giese R. F. , Snyder R. 
Published: November 2006

AbstractThe (02,11) X-ray diffraction band from a low-defect kaolinite from Cornwall (Hinckley index HI = 1·22) was examined to determine the defect structure. No combination of interlayer translations and admixing of dickite layers accurately modelled the observed diffraction pattern. Calculated diffraction patterns which gave a good agreement with the shape, position, and intensity of the observed peaks, uniformly had inter-peak intensities which were too weak. By treating the kaolinite as a mixture of low-defect (HI = 1·76) and moderate-defect (HI = 0·29) kaolinites, the agreement between the observed and calculated patterns was improved substantially. The existence of a mixture of two kaolinites was also found for a number of low-defect samples (HI > 0·4) from Georgia and Cornwall, and may be of even wider occurrence. The HI, which is very sensitive to the inner-peak intensities, does not estimate the types or abundances of various structural defects (the classical “crystallinity”), but is related directly, in a non-linear fashion, to the proportions of the two kinds of kaolinite which are present in the sample.
Clay mineral studies of the Tripoli Formation (Lower Messinian), Sicily
Authors: Azzaro E. , Bellanca A. , Neri R. 
Published: November 2006

AbstractThe characterization of clay mineral assemblages in the diatomite-dominated Tripoli Formation (Lower Messinian, central Sicily) has resulted in delineation of suites dominated by generally well-crystallized dioctahedral smectite and illite of low crystallinity, with lesser amounts of kaolinite and chlorite. These minerals are thought to have a mainly detrital origin related to the calcareous and marly formations exposed in the margins of the depositional area. Vertical fluctuations of the montmorillonite/illite ratio and changes of the crystallinity and chemical composition of these phyllosilicates support environmental interpretations from isotopic data of associated carbonates, and point to a wide variability of depositional conditions ranging from evaporating to brackish. Early diagenesis of the clay minerals was controlled by the primary composition of the sediment which, in turn, affected the porewater chemistry.
Oriented overgrowth of acicular maghemite crystals on quartz
Authors: Abreu M. M. , Figueiredo M. O. , Waerenborgh J. C. , Cabral J. M. P. 
Published: November 2006

AbstractMaghemite with acicular morphology occurs as an oriented growth on fresh quartz surfaces in the magnetic sandy fraction of the B horizon of a Typic Rhodoxeralf from southern Portugal. The maghemite was characterized by Mössbauer spectroscopy, X-ray diffraction and electron microscopy (scanning and transmission), and on the basis of a structural similarity between quartz and maghemite, a mechanism has been proposed for the formation of the oriented overgrowth. Correlation with an interpretative chemical model is discussed, assuming active sites over quartz surfaces. Infrared absorption data agree with the proposed models.
Effects of dry grinding on pyrophyllite
Authors: Pérez-Rodríguez J. L. , Madrid Sánchez del Villar L. , Sánchez-Soto P.J. 
Published: November 2006

AbstractDry grinding of pyrophyllite (Hillsboro, USA) has been studied by X-ray diffraction (XRD), specific surface area measurements (BET) and scanning electron microscopy (SEM). At the beginning of the grinding process, some effects such as delamination, gliding and folding of the layers, and decrease in particle size were detected by SEM and XRD, resulting in a large increase in specific surface area, up to a maximum of ∼60 m2·g−1. Marked changes in the structure take place between 30 and 32 mins grinding. Longer grinding times increase the degree of disorder and SEM and specific surface area data suggest that aggregation occurs. XRD results indicate that some residual order persists in the degraded structure.
Mineral phases and processes within green peloids from two Recent deposits near the Congo River Mouth
Authors: Giresse P. , Wiewiora A. , Lacka B. 
Published: November 2006

AbstractIn the Recent sediments of the Congo River estuary, the green Fe-bearing peloids containing 7 Å phases are nearer to the river mouth than the 10 Å phyllosilicates. Measurements ofd060for 7 Å minerals in various density fractions indicated a progressive transformation of kaolinite into trioctahedral 1:1 phyllosilicates in the zone with a high sedimentation rate. Projection of the chemical composition from the approximate crystallochemical formula on to a classification field confirmed the transformation of kaolinite into a 7 Å Fe-rich phase via substitution of Fe2+and Mg for Al in the octahedral sheet, with insignificant changes in the tetrahedral sheet. The resultant transition phase has a composition closer to greenalite than berthierine. The possible advancement of the evolution process was stopped by massive formation of goethite. The 10 Å minerals formed in the grains deposited in the off-shore sediments have a homogenous composition and occur in association with goethite and quartz. These peloids show an enrichment in Al although no kaolinite is present.
Characteristics of fine pores in some halloysites
Authors: Churchman G. J. , Davy T. J. , Aylmore L. A. G. , Gilkes R. J. , Self P. G. 
Published: November 2006

AbstractIsotherms were obtained for nitrogen adsorption and desorption on seven halloysite-rich samples from New Zealand and Western Australia. Calculations from these isotherms indicate that halloysites with mainly small particles (<c. 0.08 μm in width) had abundant cylindrical pores with narrow size distributions in the 5-15 nm range. They also indicate that halloysites with mainly large particles (>c. 0.1 μm in width) had few if any pores in the mesopore range (2–50 nm). Transmission electron microscopy (TEM) shows that cylindrical pores originate from the central holes in tubular particles. The TEM also suggests that slit-shaped pores can originate from the shrinkage of blocks of layers upon dehydration of halloysite.
Changes of mineralogical and surface properties of water dispersible clay after acid treatment of soils
Authors: Józefaciuk G. , Sokołowska Z. , Sokołowski S. , Alekseev A. , Alekseeva T. 
Published: November 2006

AbstractMineralogical and water adsorption properties of water dispersible clays extracted from five soils of different typology after treatment with acid to different pH levels, were studied. The mineral composition, total and divalent iron content, surface areas and average adsorption energies of water dispersible clays were complicated functions of pH, reflecting the simultaneous effects of mineral destruction and aggregate disruption processes under influence of protons on soils. The magnetic susceptibilities of water dispersible clays were the lowest at pH 2 and roughly constant at higher pH values indicating the dissolution of crystalline forms of Fe below pH 3. The broadening of the peaks of adsorption energy distribution functions with decrease in pH is related to increasing formation of amorphous material from mineral phases.
Sorptive capacity of montmorillonite for hydroxy-Cr polymers and the mode of Cr complexation
Authors: Dubbin W. E. , Goh Tee Boon 
Published: November 2006

AbstractSeparate montmorillonite suspensions were treated with CrCl3 to give seven Cr(III) concentrations. Each suspension was then titrated with 0.1 N NaOH to give a NaOH/Cr3+ molar ratio of 2.5. Montmorillonite was an effective sorbent for hydroxy-Cr species up to 1200 cmol(+)/kg; above that concentration, sorption continued, though less efficiently. However, N2-BET specific surfaces and cation exchange capacity measurements indicated that the montmorillonite could sorb significantly more than 1200 cmol(+)/kg. There was virtually no exchangeable Cr in any of the clays, suggesting that this element was covalently bonded to the siloxane surface. Infrared spectroscopy revealed a vibration at 1015–1020 cm–1 in the Cr clays which was not present in the control. This new absorption band was attributed to an attenuation of the Si–O a11 vibration caused by inner-sphere complexation of the interlayer Cr with the siloxane oxygen. Because Cr was strongly held and efficiently sorbed, montmorillonite was shown to be an effective sorbent for hydroxy-Cr polymers.
Physicochemical properties of protein-smectite and protein-Al(OH)x-smectite complexes
Authors: Violante A. , de Cristofaro A. , Rao M.A. , Gianfreda L. 
Published: November 2006

AbstractProteins (catalase, albumin, pepsin and lysozyme with different molecular weights and isoelectric points) were differently adsorbed at pH 7.0 on the clay fraction of three raw Na-saturated smectites (Crook and Uri montmorillonites and one hectorite). The adsorption isotherms of proteins on clay minerals showed typical Langmuir characteristics. Lysozyme was adsorbed under the effect of electrostatic interactions between the opposite charges of clay surfaces and protein molecules, whereas catalase and albumin were adsorbed under the effect of non-electrostatic forces. Pepsin was held in relatively high amounts only on the surfaces of hectorite. Proteins were intercalated in the interlayers spaces of smectites, usually undergoing extensive unfolding. Protein-smectite complexes showed different behaviour to heating treatment. Some complexes remained practically unchanged after heating at 200°C. Presence of ‘wrecks’ of interlayered materials was found after heating at 500°C for two hours. The amounts of proteins adsorbed on the external and interlamellar surfaces of clay minerals, partially coated with OH-Al species, were much lower than those fixed on the clean clays. Only lysozyme was intercalated in chlorite-like complexes.
Diversity of smectite origins in Late Cretaceous sediments: example of chalks from northern france
Authors: Deconinck J. F. , Chamley H. 
Published: November 2006

AbstractAccording to XRD, DTA, geochemistry and electron microscopy data of a few selected samples, three categories of smectitic clay minerals occur in the Cenomanian and Turonian chalks sampled in several sections of northern France. The first one corresponds to detrital illitesmectite mixed-layers reworked from pedogenic blankets. The second category, characterized by crystalline overgrowths around detrital particles, is especially well-developed in slowly deposited sediments. The third category, located in thin marly horizons, corresponds to Cheto-montmorillonite derived from the submarine alteration of volcanic glass. Smectitic minerals having distinct origins may therefore occur at different levels of a given formation. From these examples, the smectite-rich clay sedimentation of the Late Cretaceous is tentatively explained by the combination of favourable factors induced mainly by highstand of the sea-level. The climatic conditions, the reduction of continental areas, the development of carbonate platforms and the decrease in sedimentation rates constitute the most relevant of these factors.
Human First-Trimester Fetal MSC Express Pluripotency Markers and Grow Faster and Have Longer Telomeres Than Adult MSC
Authors: Guillot Pascale V. , Gotherstrom Cecilia , Chan Jerry , Kurata Hiroshi , Fisk Nicholas M. 
Published: November 2006

Abstract
The biological properties of stem cells are key to the success of cell therapy, for which MSC are promising candidates. Although most therapeutic applications to date have used adult bone marrow MSC, increasing evidence suggests that MSC from neonatal and mid-gestational fetal tissues are more plastic and grow faster. Fetal stem cells have been isolated earlier in development, from first-trimester blood and hemopoietic organs, raising the question of whether they are biologically closer to embryonic stem cells and thus have advantages over adult bone marrow MSC. In this study, we show that human first-trimester fetal blood, liver, and bone marrow MSC but not adult MSC express the pluripotency stem cell markers Oct-4, Nanog, Rex-1, SSEA-3, SSEA-4, Tra-1-60, and Tra-1-81. In addition, fetal MSC, irrespective of source, had longer telomeres (p &lt; .001), had greater telomerase activity (p &lt; .01), and expressed more human telomerase reverse transcriptase (p &lt; .01). Fetal MSC were also more readily expandable and senesced later in culture than their adult counterparts (p &lt; .01). Compared with adult MSC, first-trimester fetal tissues constitute a source of MSC with characteristics that appear advantageous for cell therapy.
A DCM‐Type Red‐Fluorescent Dopant for High‐Performance Organic Electroluminescent Devices
Authors: Yao Y.‐S. , Zhou Q.‐X. , Wang X.‐S. , Wang Y. , Zhang B.‐W. 
Published: November 2006

Abstract2‐(2‐tert‐Butyl‐6‐((E)‐2‐(2,6,6‐trimethyl‐2,4,5,6‐tetrahydro‐1H‐pyrrolo[3,2,1‐ij]quinolin‐8‐yl)vinyl)‐4H‐pyran‐4‐ylidene)malononitrile (DCQTB) is designed and synthesized in high yield for application as the red‐light‐emitting dopant in organic light‐emitting diodes (OLEDs). Compared with 4‐(dicyanomethylene)‐2‐tert‐butyl‐6‐(1,1,7,7,‐tetramethyljulolidyl‐9‐enyl)‐4H‐pyran (DCJTB), one of the most efficient red‐emitting dopants, DCQTB exhibits red‐shifted fluorescence but blue‐shifted absorption. The unique characteristics of DCQTB with respect to DCJTB are utilized to achieve a red OLED with improved color purity and luminous efficiency. As a result, the device that uses DCQTB as dopant, with the configuration: indium tin oxide (ITO)/N,N′‐bis(1‐naphthyl)‐N,N′‐diphenyl‐1,1′‐biphenyl‐4,4′‐diamine (NPB; 60 nm)/tris(8‐quinolinolato) aluminum (Alq3):dopant (2.3 wt %) (7 nm)/2,9‐dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline (BCP; 12 nm)/Alq3(45 nm)/LiF(0.3 nm):Al (300 nm), shows a larger maximum luminance (Lmax = 6021 cd m–2 at 17 V), higher maximum efficiency (ηmax = 4.41 cd A–1 at 11.5 V (235.5 cd m–2)), and better chromaticity coordinates (Commission Internationale de l'Eclairage, CIE, (x,y) = (0.65,0.35)) than a DCJTB‐based device with the same structure (Lmax = 3453 cd m–2 at 15.5 V, ηmax = 3.01 cd A–1 at 10 V (17.69 cd m–2), and CIE (x,y) = (0.62,0.38)). The possible reasons for the red‐shifted emission but blue‐shifted absorption of DCQTB relative to DCJTB are also discussed.