ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

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

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Striations in the Taurus molecular cloud: Kelvin-Helmholtz instability or MHD waves? (2016)
    Oxford University Press
    Details
    Publication Date: 2016-07-25
    Description: The origin of striations aligned along the local magnetic field direction in the translucent envelope of the Taurus molecular cloud is examined with new observations of 12 CO and 13 CO J = 2–1 emission obtained with the 10-m Submillimeter Telescope of the Arizona Radio Observatory. These data identify a periodic pattern of excess blue and redshifted emission that is responsible for the striations. For both 12 CO and 13 CO, spatial variations of the J = 2–1 to J = 1–0 line ratio are small and are not spatially correlated with the striation locations. A medium comprised of unresolved CO emitting substructures (cells) with a beam area filling factor less than unity at any velocity is required to explain the average line ratios and brightness temperatures. We propose that the striations are generated from the modulation of velocities and beam filling factor of the cells as a result of either the Kelvin–Helmholtz instability or magnetosonic waves propagating through the envelope of the Taurus molecular cloud. Both processes are likely common features in molecular clouds that are sub-Alfvénic and may explain low column density, cirrus-like features similarly aligned with the magnetic field observed throughout the interstellar medium in far-infrared surveys of dust emission.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    facet.materialart.
    Unknown
    A compact neutron scatter camera for field deployment (2016)
    American Institute of Physics (AIP)
    Details
    Publication Date: 2016-08-24
    Description: We describe a very compact (0.9 m high, 0.4 m diameter, 40 kg) battery operable neutron scatter camera designed for field deployment. Unlike most other systems, the configuration of the sixteen liquid-scintillator detection cells are arranged to provide omnidirectional (4π) imaging with sensitivity comparable to a conventional two-plane system. Although designed primarily to operate as a neutron scatter camera for localizing energetic neutron sources, it also functions as a Compton camera for localizing gamma sources. In addition to describing the radionuclide source localization capabilities of this system, we demonstrate how it provides neutron spectra that can distinguish plutonium metal from plutonium oxide sources, in addition to the easier task of distinguishing AmBe from fission sources.
    Print ISSN: 0034-6748
    Electronic ISSN: 1089-7623
    Topics: Electrical Engineering, Measurement and Control Technology , Physics
    Published by American Institute of Physics (AIP)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 3
    facet.materialart.
    Unknown
    Water deuterium fractionation in the high-mass star-forming region G34.26+0.15 based on Herschel/HIFI data (2014)
    Oxford University Press
    Details
    Publication Date: 2014-10-12
    Description: Understanding water deuterium fractionation is important for constraining the mechanisms of water formation in interstellar clouds. Observations of HDO and H $_2^{18}$ O transitions were carried out towards the high-mass star-forming region G34.26+0.15 with the Heterodyne Instrument for the Far-Infrared (HIFI) instrument onboard the Herschel Space Observatory , as well as with ground-based single-dish telescopes. 10 HDO lines and three H $_2^{18}$ O lines covering a broad range of upper energy levels (22–204 K) were detected. We used a non-local thermal equilibrium 1D analysis to determine the HDO/H 2 O ratio as a function of radius in the envelope. Models with different water abundance distributions were considered in order to reproduce the observed line profiles. The HDO/H 2 O ratio is found to be lower in the hot core (~3.5 10 –4 –7.5 10 –4 ) than in the colder envelope (~1.0 10 –3 –2.2 10 –3 ). This is the first time that a radial variation of the HDO/H 2 O ratio has been found to occur in a high-mass source. The chemical evolution of this source was modelled as a function of its radius and the observations are relatively well reproduced. The comparison between the chemical model and the observations leads to an age of ~10 5  yr after the infrared dark cloud stage.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 4
    facet.materialart.
    Unknown
    Numerical simulations of a shock-filament interaction (2016)
    Oxford University Press
    Details
    Publication Date: 2016-03-16
    Description: We present 3D hydrodynamic adiabatic simulations of a shock interacting with a dense, elongated cloud. We compare how the nature of the interaction changes with the filament's length and its orientation to the shock, and with the shock Mach number and the density contrast of the filament. We then examine the differences with respect to 3D spherical-cloud calculations. We find significant differences in the morphology of the interaction when M = 10 and = 10 2 : in many cases, three parallel rolls are formed, and spread furthermore apart with time, and periodic vortex shedding can occur off the ends of oblique filaments. Sideways-on filaments are accelerated more quickly, and initially lose mass more quickly than spherical clouds due to their greater surface area to volume ratio. However, at late stages, they lose mass more slowly, due to the reduced relative speed between the filament and the post-shock flow. The acceleration and mixing time-scales can vary by a factor of 2 as the filament orientation changes. Oblique filaments can achieve transverse velocities up to 10 per cent of the shock speed. Some aspects of our simulations are compared against experimental and numerical work on rigid cylinders.
    Print ISSN: 0035-8711
    Electronic ISSN: 1365-2966
    Topics: Physics
    Published by Oxford University Press
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 5
    facet.materialart.
    Unknown
    Patterning and assembly of ciliature are independent processes in hypotrich ciliates (1980)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 1980-07-11
    Description: Mirror-imaged doublets of the hypotrich ciliate Pleurotricha lanceolata were induced and analyzed with respect to the overall patterning (structural asymmetry and polarity) of the individual components of the ciliature. The overall pattern is arranged as a mirror image, but the individual components in the two halves of the doublet show the same organizational asymmetry. These data demonstrate the independence of the mechanisms for this kind of large-scale (global) patterning and control of assembly of the individual ciliary components.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Grimes, G W -- McKenna, M E -- Goldsmith-Spoegler, C M -- Knaupp, E A -- New York, N.Y. -- Science. 1980 Jul 11;209(4453):281-3.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/17807118" target="_blank"〉PubMed〈/a〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    Drug discrimination learning in lead-exposed rats (1981)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 1981-05-01
    Description: Lead acetate (0.02 or 0.5 percent) was administered to dams throughout the lactation period with half of the litters continuing on lead after weaning. Drug thresholds for d-amphetamine were determined by using the drug-discrimination learning paradigm. All the offspring that had been exposed to lead were less sensitive to the stimulus properties of d-amphetamine irrespective of whether or not they had continued on lead after weaning.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zenick, H -- Goldsmith, M -- New York, N.Y. -- Science. 1981 May 1;212(4494):569-71.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/7209554" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Behavior, Animal/drug effects ; Dextroamphetamine/*pharmacology ; Discrimination Learning/*physiology ; Disease Models, Animal ; Female ; Fetus/drug effects ; Lead Poisoning/*physiopathology ; Male ; Pregnancy ; Rats
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Imaging hippocampal mobile zinc dynamics [Neuroscience] (2014)
    National Academy of Sciences
    Details
    Publication Date: 2014-05-07
    Description: Mossy fiber termini in the hippocampus accumulate Zn2+, which is released with glutamate from synaptic vesicles upon neural excitation. Understanding the spatiotemporal regulation of mobile Zn2+ at the synaptic level is challenging owing to the difficulty of visualizing Zn2+ at individual synapses. Here we describe the use of zinc-responsive fluorescent...
    Print ISSN: 0027-8424
    Electronic ISSN: 1091-6490
    Topics: Biology , Medicine , Natural Sciences in General
    Published by National Academy of Sciences
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    Electronic Resource
    Electronic Resource
    The Phenyl-Carbon-Phenyl Angle in 1,1-Diphenylcyclopropane1 (1948)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 70 (1948), S. 2632-2634 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja01188a006
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Chromosome organization during male meiosis in Bombyx mori (1981)
    Springer
    Chromosoma 82 (1981), S. 341-351 
    Details
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Chromatin organization during male meiosis in Bombyx mori has been investigated utilizing the Miller spreading procedure. During meiotic prophase, the linear 200–300 Å chromatin fibers evident at interphase are folded into tandem arrays of approximately 7,000 loops per haploid genome. Adjacent loops visualized during early prophase are separated by 0.15–0.2 nm of nucleosomal DNA. Meiotic metaphase chromosomes display numerous loops which project radially from the central region of the chromosome suggesting that the loop conformation of prophase is maintained throughout meiosis. Spread preparations of spermatogenic stages through pachytene allow the visualization of actively transcribed ribosomal DNA. Throughout this period, these transcription units appear to be organized into loops in such a way that one active transcription unit exists on a single loop. Furthermore, there are various levels of transcription on different ribosomal loops, although the number of loops displaying active transcription remains constant throughout this period.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00285760
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Chromatin organization during meiotic prophase ofBombyx mori (1980)
    Springer
    Chromosoma 79 (1980), S. 215-224 
    Details
    ISSN: 1432-0886
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Abstract Chromatin organization during the early stages of male meiotic prophase inBombyx mori was investigated by electron microscopy. The analysis of nuclei prepared by the Miller spreading procedure, suggests that chromatin fibers which are 200–300 Å in diameter undergo an orderly folding coincident with the formation of the synaptonemal complex. In very early stages the chromatin is released in linear arrays typical of interphase chromatin material. With time loops containing 5–25 μ of B conformation DNA, initially visualized at the periphery of early meiotic prophase nuclei, aggregate into discrete foci. These foci coalesce to form the longitudinal axis of the chromosome in conjunction with the initial appearance of the axial elements of the synaptonemal complex. At pachytene, the loops are evenly distributed along the length of the chromosome and extend radially so that in well spread preparations the chromosome has a brush-like appearance. Throughout this period nascent RNP-fibers were visualized along some of the loops.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01175187
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...