Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    ISSN: 1432-8798
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary In a longitudinal survey of 11 broiler flocks, rotavirus excretion was detected by direct electron microscopic examination of faeces in 10. In most of these flocks, rotavirus excretion was first detected during the third week of life. In some flocks, infection with 2 antigenically distinct serogroups of rotavirus was demonstrated. In a more detailed survey of a 34,000 bird broiler crop, rotavirus excretion was detected intermittently from 9–50 days. Infection with 4 different RNA electropherotypes of rotavirus occurred in waves with each wave of infection lasting about 1 week. Analysis of representatives of the 4 different electropherotypes by cross-immunofluorescence indicated that each electropherotype represented an antigenically distinct serogroup. Two of these serogroups were represented by the previously characterised Ch 1 and 132 chicken rotavirus isolates. The other 2 serogroups have not been previously recognised.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1460-9568
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: A new member of the fibroblast growth factor (FGF) family, FGF-13, has been molecularly cloned as a result of high throughput sequencing of a human ovarian cancer cell library. The open reading frame of the novel human gene (1419 bp) encodes for a protein of 216 a.a. with a molecular weight of 22 kDa. The FGF-13 sequence contains an amino-terminal hydrophobic region of 23 a.a. characteristic of a signal secretion sequence. FGF-13 is most homologous, 70% similarity at the amino acid level, to FGF-8. Northern hybridization analysis demonstrated prominent expression of FGF-13 in human foetal and adult brain, particularly in the cerebellum and cortex. In proliferation studies with BaF3 cells, FGF-13 preferentially activates cell clones expressing either FGF receptor variant, 3-IIIc or 4. The signal transduction pathways of FGF-13 and FGF-2 were compared in rat hippocampal astrocytes. The two FGFs induce an equivalent level of tyrosine phosphorylation of mitogen-activated protein kinase (MAPK) and c-raf activation. However, FGF-13 is more effective than FGF-2 in inducing the phosphorylation of phospholipase C-gamma (PLC-γ). Treatment of neuronal cultures from rat embryonic cortex with FGF-13 increases the number of glutamic acid decarboxylase immunopositive neurons, the level of high-affinity gamma-aminobutyric acid (GABA) uptake, and choline acetyltransferase enzyme activity. The GABAergic neuronal response to FGF-13 treatment is rapid with a significant increase occurring within 72 h. We have identified a novel member of the FGF family that is expressed in the central nervous system (CNS) and increases the number as well as the level of phenotypic differentiation of cortical neurons in vitro.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    ISSN: 1460-9568
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The purpose of this study was to further characterize the phenotype of rats that have experienced prolonged postweaning social isolation, a paradigm that produces changes relevant to neuropsychiatric disorders. At weaning, male Wistar rats from three litters were housed socially (n = 12) or in isolation (n = 13) for 10 weeks. Isolated rats could see, hear and smell other rats. A sophisticated analysis of gait revealed that the stride duration was increased in isolates (12%, P = 0.0024) as a result of increased stance duration (18%, P = 0.0005), but there was no difference in vertical reaction force or velocity. Adrenal glands were heavier in isolates (19%, P = 0.0047). There was no difference in cross-sectional area of the brain or lateral ventricles anywhere along the anterior–posterior axis. All experiments and analysis were performed blind to housing condition. This is the first study to demonstrate that socially isolated rats have an abnormal gait. Further analysis, including pharmacological manipulation, is needed in order to understand the nature of the abnormality.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Geophysical prospecting 25 (1977), S. 0 
    ISSN: 1365-2478
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Geosciences , Physics
    Notes: The contribution of electromagnetic phase comparison techniques to distance measuring is reviewed in an historical context. Special emphasis is accorded the new class of near infra-red electro-optic instruments suited to the measurement of distances under 2 km with an accuracy of a few millimetres. Principles of operation, sources of error, and practical applications are discussed.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 1434-4483
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Summary  An evaluation of the impacts of weather on pollution, specifically, ozone and total suspended particulates concentration for Summer, is examined in four cities in the U.S.: Birmingham, Cleveland, Philadelphia, and Seattle. These cities were selected because of their different climate regimes and their generally good pollutant and meteorological datasets. This paper uses a synoptic climatological approach, which combines a number of atmospheric factors, to better identify the relationships between atmospheric pollution and climatological conditions. Synoptic events represent holistic units of atmospheric conditions which commonly occur at a given locale, and possess specific weather and pollution characteristics. A number of weather variables, including temperature, are used in the development of a synoptic index, which can be used to identify synoptic events associated with specific pollution episodes. Results from the analysis illustrate that there is a substantial difference in pollution loads under different synoptic patterns, and that the cities do have substantially different relationships. Information from this study could be used to assist in the analysis of the differential impacts of weather and pollution upon human morbidity. Specific information as to the linkages between the synoptic weather patterns, pollution concentrations, and human health could be used in the development of weather/health watch-warning systems to alert the public that a synoptic episode is imminent.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1617-4623
    Keywords: Key words Cytochrome b6/f complex ; aadA ; Cytochrome b6 ; Subunit IV
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Translation initiation in chloroplasts is a complex process involving a variety of cis-elements and trans-acting factors. Many chloroplast mRNAs are processed products of polycistronic primary transcripts, but the functional requirement for processing is mostly enigmatic. In tobacco, the petB and petD genes, which encode subunits of the cytochrome b 6 /f complex, are transcribed from the psbB operon, whose primary transcript is processed into products including di- or tricistronic, but not monocistronic, petB and petD mRNAs. To begin to identify elements important for petB and/or petD translation, we generated tobacco chloroplast transformants by inserting selectable aadA marker cassette in the petB-petD intergenic region. The resulting plants required sucrose for growth, and their phenotypes depended on the orientation of the aadA cassette. When aadA was inserted in the same transcriptional orientation as the psbB operon, petB and petD mRNAs were abundantly produced but aberrant in size, and only 25% of the wild-type amount of the cytochrome b 6 /f complex accumulated. With the aadA cassette in the opposing orientation, however, very little petD mRNA accumulated, and the cytochrome b 6 /f complex was undetectable. Polysome analysis suggested that petD mRNAs in both transformants were poorly translated, indicating that the intergenic region contains essential translational elements.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Low-temperature deposition of TiN by reactive evaporation or sputter deposition onto amorphous substrates leads to highly underdense layers which develop mixed 111/002 orientations through competitive growth. In contrast, we demonstrate here the growth of low-temperature (450 °C) fully dense polycrystalline TiN layers with complete 111 texture. This was achieved by reactive magnetron sputter deposition using a combination of: (1) highly oriented 25-nm-thick 0002 Ti underlayers to provide 111 TiN orientation through texture inheritance (local epitaxy) and (2) high flux (JN2+/JTi=14), low-energy (EN2+(similar, equals)20 eV), N2+ ion irradiation in a magnetically unbalanced mode to provide enhanced adatom diffusion leading to densification during TiN deposition. The Ti underlayers were also grown in a magnetically unbalanced mode, in this case with an incident Ar+/Ti flux ratio of 2 and EAr+(similar, equals)11 eV. All TiN films were slightly overstoichiometric with a N/Ti ratio of 1.02±0.03. In order to assess the diffusion-barrier properties of dense 111-textured TiN, Al overlayers were deposited without breaking vacuum at 100 °C. Al/TiN bilayers were then annealed at a constant ramp rate of 3 °C s−1 to 650 °C s−1 and the interfacial reaction between Al and TiN was monitored by in situ synchrotron x-ray diffraction measurements. As a reference point, we find that interfacial Al3Ti formation is observed at 450 °C in Al/TiN bilayers in which the TiN layer is deposited directly on SiO2 in a conventional magnetically balanced mode and, hence, is underdense with a mixed 111/002 orientation. However, the onset temperature for interfacial reaction was increased to 610 °C in bilayers with fully dense TiN exhibiting complete 111 preferred orientation. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A test stand for development of ion sources for radioactive beams is currently being commissioned at Argonne. It is located at the Physics Division's Dynamitron accelerator which will be used as a neutron generator with a flux of up to 1011 neutrons per second created by reactions of 4 MeV deuterons on various targets with beam currents of up to 100 μA. The primary targets will be located adjacent to heated secondary targets inside an on-line ion source. With this neutron-generator facility it will be possible to produce radioactive beams of various isotopes, such as 6He, 24Na, and neutron-rich fission fragments. For example, with a secondary target of uranium carbide containing 25 g of natural or depleted uranium the yields of individual isotopes in the target will be about 107/s for isotopes such as 132Sn, 140Xe, and 142Cs, near the peak of the fission distribution. The ion sources to be evaluated will be located within a shielded cave with walls consisting of 30 cm of steel plus 60 cm of concrete to attenuate the prompt neutron radiation by a factor of about 104. Secondary beams of radioactive fission fragments with intensities on the order of 106/s per isotope will be extracted in the 1+ charge state at energies of 20 keV and mass separated with a Danfysik mass separator. Light isotopes, such as 6He and 24Na, can be produced via (n,α) and (n,p) reactions on appropriate target materials. Commissioning began with measurements of fission yields from primary targets of C, Be, BeO, and BN. A surface ionization source which is a variation of the one used in the TRISTAN on-line mass seperator facility at Brookhaven National Laboratory has been installed and tested with stable Rb and Cs beams. The isotope separator was also commissioned with these beams. The development program will include emittance measurements and source optimization, initially with stable beams, and target-delay-time and release-efficiency measurements for various target/secondary-beam systems. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: A direct ion plasma sputtering effect has been observed in an electron cyclotron resonance ion source and developed into a reliable and simple method for producing ion beams from some solid materials. We describe the ion sputtering technique used with the Argonne Tandem Linac Accelerator System Positive Ion Injector Electron Cyclotron Resonance ion source to produce, to date, stable beams of nickel, silver, tellurium, gold, lead, and bismuth and present the results obtained in test cases. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
  • 10
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 64 (1993), S. 2387-2388 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: We describe a novel XY micropositioning stage which operates using a single piezoelectric actuator to produce slip-stick motion. The stage can be moved in steps as small as 20 nm over an area of 9 mm×9 mm, at translation speeds of up to 0.5 mm/s. Cross coupling between axes is negligible, and the threshold voltage for movement is typically 10 V or less. The device is simple in construction and requires no precision components. The stage is small and robust, requires no mechanical connections, and offers the unique advantage in scanning tunneling microscopy and atomic force microscopy applications of being able to provide a Z displacement of some microns.
    Type of Medium: Electronic Resource
    Signatur Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...