bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhibition of Chemokine Expression by Adenovirus Early Region Three (E3) Genes
Authors: Lesokhin Alexander M. , Delgado-Lopez Fernando , Horwitz Marshall S. 
Published: July 2002

ABSTRACTAdenoviruses (Ad) have a variety of immunoregulatory genes, many of which are clustered in a 3.5-kb segment of DNA known as early region 3 (E3). Ad E3 codes for proteins that downregulate surface expression of class I major histocompatibility antigens and also inhibit tumor necrosis factor alpha (TNF-α)- and Fas-induced cytolysis. We were interested in determining whether chemokine production or activity might also be inhibited by Ad E3 and we have studied this function in a human astrocytoma cell line, U373. Astrocytes constitute a part of the blood-brain barrier, and chemokines (IP-10, IL-8, MCP-1-4, and MIPs) expressed by them may contribute to leukocyte infiltration within the brain during inflammation. When U373 cells are activated by the proinflammatory molecule TNF-α, the increase in chemokine MCP-1, IL-8, and IP-10 transcripts is blocked by a recombinant Ad expressing the E3 genes under cytomegalovirus promoter control. Comparable Ads expressing green fluorescent protein in place of E3 have no effect on these chemokines. Ads also have been extensively studied as gene therapy vectors and most have a deletion of the E3 region to permit the insertion of larger fragments of foreign DNA. Our results suggest that construction of Ad vectors to include E3 expression cassettes will improve the efficacy and safety of such viral-based gene therapy protocols.
Heparan Sulfate Mediates Infection of High-Neurovirulence Theiler's Viruses
Authors: Reddi Honey V. , Lipton Howard L. 
Published: July 2002

ABSTRACT
The mechanisms by which Theiler's murine encephalomyelitis virus (TMEV) binds and enters host cells and the molecules involved are not completely understood. In this study, we demonstrate that the high-neurovirulence TMEV GDVII virus uses the glycosaminoglycan heparan sulfate (HS) as an attachment factor that is required for efficient infection. Studies based on soluble HS-mediated inhibition of attachment and infection, removal of HS with specific enzymes, and blocking with anti-HS antibodies establish that HS mediates GDVII virus entry into mammalian cells. Data from defined proteoglycan-deficient Chinese hamster ovary mutant cells further support the role of HS in GDVII infection and indicate that the extent of sulfation is critical for infection. Neuraminidase treatment of proteoglycan-deficient cells restores permissiveness to GDVII virus, indicating that sialic acid hinders direct access of virus to the protein entry receptor. A model of the potential steps in GDVII virus entry into mammalian cells involving HS is proposed.
The Relationship between Simian Immunodeficiency Virus RNA Levels and the mRNA Levels of Alpha/Beta Interferons (IFN-α/β) and IFN-α/β-Inducible Mx in Lymphoid Tissues of Rhesus Macaques during Acute and Chronic Infection
Authors: Abel Kristina , Alegria-Hartman Michelle J. , Rothaeusler Kristina , Marthas Marta , Miller Christopher J. 
Published: July 2002

ABSTRACTTo define the role of alpha/beta interferons (IFN-α/β) in simian immunodeficiency virus (SIV) infection, IFN-α and IFN-β mRNA levels and mRNA levels of Mx, an antiviral effector molecule, were determined in lymphoid tissues of rhesus macaques infected with pathogenic SIV. IFN-α/β responses were induced during the acute phase and persisted in various lymphoid tissues throughout the chronic phase of infection. IFN-α/β responses were most consistent in tissues with high viral RNA levels; thus, IFN-α/β responses were not generally associated with effective control of SIV replication. IFN-α/β responses were differentially regulated in different lymphoid tissues and at different stages of infection. The most consistent IFN-α/β responses in acute and chronic SIV infection were observed in peripheral lymph nodes. In the spleen, only a transient increase in IFN-α/β mRNA levels during acute SIV infection was observed. Further, IFN-α and IFN-β mRNA levels showed a tissue-specific expression pattern during the chronic, but not the acute, phase of infection. In the acute phase of infection, SIV RNA levels in lymphoid tissues of rhesus macaques correlated with mRNA levels of both IFN-α and IFN-β, whereas during chronic SIV infection only increased IFN-α mRNA levels correlated with the level of virus replication in the same tissues. In lymphoid tissues of all SIV-infected monkeys, higher viral RNA levels were associated with increased Mx mRNA levels. We found no evidence that monkeys with increased Mx mRNA levels in lymphoid tissues had enhanced control of virus replication. In fact, Mx mRNA levels were associated with high viral RNA levels in lymphoid tissues of chronically infected animals.
Recovery of Virulent and RNase-Negative Attenuated Type 2 Bovine Viral Diarrhea Viruses from Infectious cDNA Clones
Authors: Meyer Christiane , von Freyburg Martina , Elbers Knut , Meyers Gregor 
Published: July 2002

ABSTRACTCloned cDNA derived from the genome of the virulent type 2 bovine viral diarrhea virus (BVDV) strain NY'93/C was sequenced and served for establishment of the infectious cDNA clone pKANE40A. Virus recovered from pKANE40A exhibited growth characteristics similar to those of wild-type BVDV NY'93/C and proved to be clinically indistinguishable from the wild-type virus in animal experiments. A virus mutant in which the RNase residing in the viral glycoprotein Ernswas inactivated, revealed an attenuated phenotype. The plasmid pKANE40A represents the first infectious cDNA clone established for a type 2 BVDV and offers a variety of new approaches to analyze the mechanisms of BVDV-induced disease in cattle.
Halogenation of Tris(amido)tantalacarboranes with Dihalomethanes CH2X2 (X = Cl, Br)
Authors: Fox Mark A. , Goeta Andrés E. , Hughes Andrew K. , Malget John M. , Wade Ken 
Published: July 2002

Slow reactions of isomeric metallacarboranes of general formulae [(NMe2)3TaC2B9H11] (3 isomers) and [(NMe2)3TaC2B9H10Me] (3 isomers) with CD2Cl2 afford quantitative yields of monochloro complexes [Cl(NMe2)2TaC2B9H11] and [Cl(NMe2)2TaC2B9H10Me]. Exposure to CD2Cl2 for months leads to solutions containing about 70% of the dichlorides in three cases. More prolonged exposure of these and the other monochlorides leads to a mixture of boron-substituted complexes. Hydrolysis of [3,3,3-(NMe2)3-3,1,2-TaC2B9H11] by moist toluene results in the formation of the oxo-bridged complex 3,3'-[3,3-(NMe2)2-3,1,2-TaC2B9H11]2(μ-O), characterised by single-crystal X-ray crystallography. The limited solubility of the latter complex in CD2Cl2 eliminates the presence of this compound in the reaction of [3,3,3-(NMe2)3-3,1,2-TaC2B9H11] with CD2Cl2. The reaction of [2,2,2-(NMe2)3-2,1,12-TaC2B9H11] with CH2Br2 in C6D6 quantitatively yields the monobromide [2-Br-2,2-(NMe2)2-2,1,12-TaC2B9H11]. Prolonged reaction with CH2Br2 leads directly to isomeric boron-substituted complexes with no evidence for dibromides. The influence on 11B, 13C and 1H NMR chemical shifts of replacing an amide group in [(NMe2)3TaC2B9H11] with chloride to give [Cl(NMe2)2TaC2B9H11] is also discussed.
Cancer incidence and magnetic field exposure in industries using resistance welding in Sweden
Authors: Håkansson N , Floderus B , Gustavsson P , Johansen C , Olsen J H 
Published: July 2002

Aims:To investigate cancer incidence in workers exposed to high levels of extremely low frequency magnetic fields (ELF-MF).Methods:A cohort based on the engineering industry was established. Industries assumed to use resistance welding in production were chosen in order to increase the prevalence of high exposed subjects and to reduce the influence of confounding factors. All men and women employed in these branches during 1985–94 were selected, 537 692 men and 180 529 women. Occupation, based on census information from 1980, 1985, and 1990, was linked to a job exposure matrix on ELF-MF. Four exposure groups were used by stratifying on mean workday ELF-MF exposure, using the lowest exposure group as reference. Cancer incidence was obtained by linkage to the Swedish Cancer Registry.Results:Men in the very high exposure group showed an increased incidence of tumours of the kidney, pituitary gland, and biliary passages and liver; for these cancer sites an exposure–response relation was indicated. Women in the very high exposure group showed an increased incidence of astrocytoma I–IV, with a clear exposure–response pattern. An association was suggested in the high exposure group only, for cancer of the corpus uteri and multiple myeloma. Decreased risks in the very high exposure group among men were found for cancer of the colon and connective tissue/muscle.Conclusions:The results on cancer of the liver, kidney, and pituitary gland among men are in accordance with previous observations. Regarding brain tumours and leukaemia, the outcome for women provided further support of an association. The hypothesis of a biological mechanism involving the endocrine system was partly supported.
Influence of thrombolytic therapy on the patterns of ventricular septal rupture after acute myocardial infarction
Authors: Rhydwen G R , Charman S , Schofield P M 
Published: July 2002

Abstract

Background
Post-myocardial infarction ventricular septal defect (VSD) complicates ∼2% of myocardial infarctions. Thrombolytic therapy may accelerate the time from myocardial infarction to VSD formation. The effects of thrombolytic therapy in patients with a post-myocardial infarction VSD were investigated.

Method
Demographic, procedural, and event data were retrospectively analysed in patients transferred to a regional cardiothoracic centre with the diagnosis of post-myocardial infarction VSD over five years.

Results
Twenty nine patients were analysed; 15 received thrombolytic therapy: 10 (&lt;12 hours) early and five (≥12 hours) late. The median time to post-myocardial infarction VSD was shorter with thrombolytic therapy at 1 v 5.5 days (p=0.01). The median time to post-myocardial infarction VSD was shorter with early compared with late thrombolytic therapy at 1 v 6 days (p&lt;0.01). There was no difference between late and no thrombolytic therapy, 5.5 v 6 days. Patients treated with thrombolytic therapy had a trend towards higher mortality at 11/15 (73%) compared with 5/14 (36%) (p=0.066). Twenty five (86%) patients had surgery. All four not having surgery died. Surgical survival was 13/25 (52%) at discharge and six months of follow up. Within the surgical group survival with prior thrombolytic therapy was 4/25 (25%) and 9/13 (69%) without (p=0.07).

Conclusion
There appears to be an earlier presentation of post-myocardial infarction VSD when thrombolytic therapy has been used. An early presentation can carry a worse prognosis and may have implications for the identification and treatment of this life threatening complication.
Production of negatively charged particles in nucleusnucleus collisions at 200A GeV
Authors: Liu F -H 
Published: July 2002

Three isotropic emission fireballs are used to describe the rapidity (or pseudorapidity) and transverse momentum distributions of negatively charged particles produced in nucleusnucleus collisions at high energy. The calculated results are compared and shown to be in agreement with the experimental data of 16OAu, 32SS, and 32SAg collisions at 200A GeV. PACS Nos.: 25.75-q, 24.10Pa
The optimal length of a rifle barrel
Authors: Mohazzabi P , Shefchik B M 
Published: July 2002

A simple thermodynamic model for projectile propulsion inside a rifle barrel results in a functional relationship between the muzzle speed of the rifle and its barrel length. This relationship is in excellent agreement with the existing experimental data over a wide range of barrel lengths. PACS No.: 45.40.Gj, 89.00
Studies for the Odin sub-millimetre radiometer. II. Retrieval methodology
Authors: Baron Ph. , Ricaud Ph. , Noë J de la , Eriksson J EP , Merino F , Ridal M , Murtagh D P 
Published: July 2002

This paper presents the first algorithm developed to retrieve atmospheric vertical profiles of trace gases from calibrated spectra measured by the sub-millimetre radiometer (SMR) onboard the Odin satellite. An estimation of atmospheric profiles is obtained by means of an inversion of the spectra using the Optimal Estimation Method. Great attention is paid to the study of the simultaneous retrieval of several species and nonlinearity effects. The measurement response is defined to give the altitude domain of a good retrieval. Main sources of measurement and forward model errors are characterized and separated into two categories: the fixed errors and the variable errors. We define a standard retrieval strategy that can be applied to theoretically investigate any frequency band of any observing Odin mode. For each frequency band, two categories of species are defined: the target species, i.e., the main species to be retrieved, and the interfering species, i.e., molecules emitting an interfering radiance in the observed band. The standard code is based upon an inversion of spectra using a linearized forward model and simultaneously estimates target species and interfering species. As an example, inversions of synthetic noise-free spectra of ozone and chlorine monoxide within an autocorrelator band ranging from 501.18 to 501.58 GHz are shown to behave as expected in the middle stratosphere and in the lower mesosphere. The error analysis shows retrieval limitations in the lower stratosphere that are mainly induced by the high sensitivity of the retrieval to parameters such as tangent height, accuracy in the vertical profile of the interfering species, and spectral parameters of both target lines and interfering lines. PACS Nos.: 42.68Ay, 07.07Df, 07.57Kp
A method for recovering stratospheric minor species densities from the Odin/OSIRIS scattered-sunlight measurements
Authors: McDade I C , Strong K , Haley C S , Stegman J , Murtagh D P , Llewellyn E J 
Published: July 2002

A method for recovering minor species density profiles in the stratosphere from observations made with the OSIRIS (optical spectrograph and infrared imager system) instrument on the Odin satellite is described. The OSIRIS instrument measures limb radiances of scattered sunlight over the spectral range 2800 to 8000 Å, for tangent heights ranging from 10 to 100 km. We describe how the limb spectra may be processed using the DOAS (differential optical absorption spectroscopy) technique to derive apparent column densities for the minor atmospheric constituents O3, NO2, OClO, and BrO. We also show how these column densities, measured over a range of tangent heights, may be inverted using an iterative least-squares technique to determine the local density profiles. The procedures are illustrated using simulated limb radiances generated with a realistic OSIRIS instrument model. PACS Nos.: 42.68Mj, 94.10Dy
Microwave temperature and pressure measurements with the Odin satellite: I. Observational method
Authors: Pardo J R , Ridal M , Murtagh D , Cernicharo J 
Published: July 2002

The Odin satellite is equipped with millimetre and sub-millimetre receivers for observations of several molecular lines in the middle and upper atmosphere of our planet (~25100 km, the particular altitude range depending on the species) for studies in dynamics, chemistry, and energy transfer in these regions. The same receivers are also used to observe molecules in outer space, this being the astrophysical share of the project. Among the atmospheric lines that can be observed, we find two corresponding to molecular oxygen (118.75 GHz and 487.25 GHz). These lines can be used for retrievals of the atmospheric temperature vertical profile. In this paper, we describe the radiative-transfer modeling for O2 in the middle and upper atmosphere that we will use as a basis for the retrieval algorithms. Two different observation modes have been planned for Odin, the three-channel operational mode and a high-resolution mode. The first one will determine the temperature and pressure on an operational basis using the oxygen line at 118.75 GHz, while the latter can be used for measurements of both O2 lines, during a small fraction of the total available time for aeronomy, aimed at checking the particular details of the radiative transfer near O2 lines at very high altitudes (>70 km). The Odin temperature measurements are expected to cover the altitude range ~3090 km. PACS Nos.: 07.57Mj, 94.10Dy, 95.75Rs
Vertical polarization for transient plane waves obliquely incident on a conductive half-space
Authors: Abo-Seida O M 
Published: July 2002

The vertical polarization for transient plane waves obliquely incident on a conductive half-space is analytically evaluated. It is assumed that the dispersive half-space is homogenous. Starting with the transmitted waves in the frequency domain, the corresponding time-domain expressions are first represented as inverse Laplace transforms. The integrals of the fields are numerically solved and the results are represented graphically. PACS Nos.: 41.20Jb, 42.25Bs, 42.25Gy, 44.05+e
Anharmonic coherent states and E ε JahnTeller coupling
Authors: Avram N M , Draganescu Gh. E , Avram C N 
Published: July 2002

The octahedral JahnTeller system with E [Formula: see text] ε coupling is studied in the frame of the anharmonic vibrations described by a Morse potential using anharmonic coherent states. The energy levels have been established. PACS Nos.: 31.30Gs, 71.70Ej, 42.50Ar, 42.50Ct, 33.20Wr
Laser spectroscopic measurements of hyperfine structure in Pr II
Authors: Rivest R C , Izawa M R , Rosner S D , Scholl T J , Wu G , Holt R A 
Published: July 2002

We have used fast-ion-beam laser spectroscopy to measure the hyperfine structure of 36 transitions in Pr II in the wavelength range 420460 nm, obtaining the hyperfine constants of 8 odd-parity levels in the range 05079 cm1 and 32 even-parity levels in the range 22 04028 578 cm1 with a typical accuracy of 0.2%. These will find useful application in stellar elemental abundance studies. PACS Nos.: 32.30-r, 32.10-f
Microwave temperature and pressure measurements with the Odin satellite: II. Retrieval method
Authors: Ridal M , Murtagh D P , Merino F , Pardo J R , Pagani L 
Published: July 2002

The millimetre receiver on the Swedish satellite Odin, will be used for detection of the 118.750 GHz oxygen line. The temperature and pressure will be determined from the output of a three-channel filter bank measurement. One frequency bin is centred over the emission-line frequency while the other two cover parts of the line wing, where the opacity is less, providing a useful signal at lower altitudes. The bandwidth of each channel is 40 MHz. The signal in the frequency bin covering the line centre is modeled by a high-resolution model including the Zeeman effect, developed by the Observatoire de ParisMeudon. The other two 40 MHz bins are modeled using the much faster standard Odin forward model, developed at the Department of Meteorology at Stockholm University together with Chalmers University of Technology. The operational retrievals employ an iterative method that uses simulated signals from a reference atmosphere as a lookup table for the pressure. The temperature is then calculated from the equation of hydrostatic equilibrium, and a new lookup table computed. This process is repeated until a convergence criterion is reached. Simulations, including known error sources, show that the temperature can be retrieved with a root mean square (rms) around 3 K, in the altitude range ~ 2590 km using the operational temperature retrieval method (the filter bank method). A sub-millimetre receiver on board Odin will also be used to observe the oxygen line at 487.249 GHz. Both this line and the 118.750 GHz line can be observed in high resolution (150 kHz) for detailed studies of the Zeeman splitting. Retrievals from the high-resolution measurements are expected to give a precision of ± 2 K rms at that resolution. However, this kind of observation will occupy an entire spectrometer and will not be made on a regular basis. PACS Nos.: 07.57Yb, 94.10Dy, 95.75Rs
Mesospheric ozone: Determination from orbit with the OSIRIS instrument on Odin
Authors: Khabibrakhmanov I K , Degenstein D A , Llewellyn E J 
Published: July 2002

The analysis of the data from the optical spectrograph and infrared imager system (OSIRIS) that will fly on the Odin satellite requires special attention as many of the measurements will be made in regions of the atmosphere that are relatively close to terminator. Under these conditions the photochemical processes in the upper atmosphere that are responsible for much of the oxygen infrared atmospheric band airglow emission are nonstationary. It is this latter aspect that complicates the retrieval of the mesospheric ozone profile from the OSIRIS observations. However, a tomographic analysis technique that has been developed specifically for the Odin project allows accurate recovery of local volume emission rates in the orbit plane. It is shown that the tomographic analysis technique can be combined with nonstationary atmospheric photochemistry models to recover the mesospheric ozone profile near the terminator. PACS Nos.: 94.10Fa, 94.10Rk
Numerical investigations into static and quasistatic problems of two-dimensional dry elastic frictional contact
Authors: Schlesinger M , McAven L F , Yao Y 
Published: July 2002

A numerical-modelling method is developed to investigate the stress of the static-equilibrium state of the two-dimensional frictional contact problem achieved through a quasistatic process of increasing loading. The problem of relative tangential displacement between particles on the two contact surfaces is addressed. This scheme relies on solving each of the two contact solids in turn and iterating back and forth. The solutions for the two elastic bodies are connected through the surface traction and surface deformation. The contact surface is approximated by a cubic spline, and friction is modelled using the classical Coulomb friction law. Variational inequalities and finite-element methods are used to implement this scheme and are solved by an optimization method. In addition, the distinction between Cauchy stress and PiolaKirchoff stress is taken into account and discussed. A numerical investigation is conducted into the stress dependence on the loading conditions and geometries of the solids. The results from the numerical examples deviate from Hertz theory and previous reports. Stress is shown to be sensitive to the loading distribution and geometry of contact solids. Therefore, it suggests that an accurate analysis of the dry frictional contact problem requires a refined knowledge of the loading conditions and the total geometry of both solids. PACS Nos.: 03.40D, 46.30P, 62.20P
LEPTONS WITH E > 200 MEV TRAPPED IN THE SOUTH ATLANTIC ANOMALY
Authors: FIANDRINI E. , ESPOSITO G. 
Published: July 2002

For the first time accurate measurements of electron and positron fluxes in the energy range 0.2 ÷ 10 GeV have been performed with the Alpha Magnetic Spectrometer (AMS) at altitudes of 370 ÷ 390 km in the geographic latitude interval ±51.7°. We focused on the under-cutoff lepton fluxes inside the region of the South Atlantic Anomaly (SAA), defined as region where the local magnetic field B ≤ 0.26 G. A clear transtion region from stably-trapped flux typical of the lnner Van Allen Belts to quasi-trapped flux typical underneath the Van Allen Belts is observed in the SAA up to energies O(Gev). The observations strongly support positrons abundance in the Inner Van Allen Belts, both in the stably trapped component and in the quasi-trapped one. The flux maps as a function of the canonical adiabatic variables L, αo are presented for the intervval 0.95 < L < 3, 0° < αo < 90° for electrons (E < 10 GeV) and positrons (E < 3 GeV). The results are compared with existing data at lower energies.