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
Filter
  • Life and Medical Sciences  (3)
  • Space Sciences (General)  (2)
  • Determinacy problem  (1)
  • 1
    facet.materialart.
    Unknown
    Seeking Signs of Life on Mars: A Strategy for Selecting and Analyzing Returned Samples from Hydrothermal Deposits (2018)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: Highly promising locales for biosignature prospecting on Mars are ancient hydrothermal deposits, formed by the interaction of surface water with heat from volcanism or impacts. On Earth, they occur throughout the geological record (to at least approx. 3.5 Ga), preserving robust mineralogical, textural and compositional evidence of thermophilic microbial activity. Hydrothermal systems were likely present early in Mars' history, including at two of the three finalist candidate landing sites for M2020, Columbia Hills and NE Syrtis Major. Hydrothermal environments on Earth's surface are varied, constituting subaerial hot spring aprons, mounds and fumaroles; shallow to deep-sea hydrothermal vents (black and white smokers); and vent mounds and hot-spring discharges in lacustrine and fluvial settings. Biological information can be preserved by rapid, spring-sourced mineral precipitation, but also could be altered or destroyed by postdepositional events. Thus, field observations need to be followed by detailed laboratory analysis to verify potential biosignatures. See Attachment
    Keywords: Space Sciences (General)
    Type: JSC-E-DAA-TN52589 , International Mars Sample Return Conference; Apr 25, 2018 - Apr 27, 2018; Berlin; Germany
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    Electronic Resource
    Electronic Resource
    Physiological Relevance of Uniform Elastic Tube-Models to Infer Descending Aortic Wave Reflection: A Problem of Identifiability (2000)
    Springer
    Annals of biomedical engineering 28 (2000), S. 512-523 
    Details
    ISSN: 1573-9686
    Keywords: Arterial pulse wave propagation ; Determinacy problem ; Arterial effective reflection site ; Vascular impedance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine , Technology
    Notes: Abstract A uniform, frictional elastic tube terminating in a pure resistor (model A), was compared with a uniform, frictionless elastic tube, terminating in a first-order low-pass filter load (model B). The aim was to address an identifiability problem in uniqueness of parameter estimates and to evaluate the physiological meaning of tube-length estimates obtained from these models applied to the descending aortic circulation. Measurements of high descending aortic pressure and flow were taken from three anaesthetized, open-chest dogs and used to estimate the model parameters. A simultaneous measurement of terminal aortic pressure was used to estimate the foot-to-foot pulse wave velocity. A flow-fitting procedure yielded a multiplicity of equivalent solutions for the wave transit time across the transmission tubes ( $${\tau }_{ai}$$ for model A and $${\tau }_{bi}$$ for model B, $$i = 0,1,2,...,N,...$$ and the related tube-lengths $$d_{ai}$$ and $$d_{bi}$$ respectively. The tube length represents the distance to an effective reflection site (effective length) of the descending aortic circulation. Assuming that this length should be no longer than the dimensions of the body, the lowest estimates (i=0) of wave transit time and tube length (average ±SE: $${\tau }_{ao} = 85.7 \pm 10.8{ms}$$ and $$d_{ao} = 53.4 \pm 3.7 {cm}$$ for model A; $${\tau }_{bo} = 46.6 \pm 6.7 {ms}$$ and $$d_{bo} = 29.1 \pm 3.5{cm}$$ for model B) were identifiable as unique and acceptable solutions. Model A located the effective reflection site a few centimeters below the terminal aortic region. This location is inconsistent with the use of a pure resistor as a tube's terminal load. Further, relatively high estimates of longitudinal frictional losses violated the assumption of small losses across the transmission path and yielded an unphysiological mean-pressure drop of 7.1 $$\pm$$ 2.3mm Hg. The estimates of $$d_{bo}$$ provided by model B located the effective reflection site near the origin of the renal arteries. The model-predicted pressure wave at this location approximated the measured pressure. Thus, model B represents a significant improvement over model A as a tool to infer wave travel and reflection in the descending aortic circulation. © 2000 Biomedical Engineering Society. PAC00: 8719Uv, 4760+i
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1114/1.291
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Characterization of the dipnoi, a monophyletic group (1986)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 190 (1986), S. 25-37 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Fossil and extant dipnoans form a well-defined group of osteichthyans. Tooth plates, a feature in common for extant and the majority of fossil dipnoans, are not found in all dipnoans. Nevertheless primitive dipnoans can be defined by 21 characters of the head skeleton: bone arrangement in the posterior part of the skull roof, relation between supraorbital sensory line and bones, five extrascapulars, ossified (soft in post-Devonian dipnoans) upper lip, lack of premaxilla and maxilla, number and arrangement of bones in cheek region, lack of coronoids, the presence of an adsymphysial plate, ossified (soft in post-Devonian dipnoans) lower lip, relationship of oral and mandibular sensory canal to “infradentaries,” course of neurovascular system in lower jaw, symphysial tubuli in lower jaw, gular-shaped submandibulars, anterior naris at the edge and posterior naris within the mouth, median contact of pterygoids back to jaw articulation, posterior position of parasphenoid (buccohypophysial foramen very anterior in parasphenoid), unpaired “vomer,” autostyly, neurocranial support of posterior dermal skull roof, no isolated hypobranchials, and pharyngobranchials reduced or lacking. These 21 features distinguish the dipnoans from all other sarcopterygians. The Lower Devonian genus Diabolepis, which is said by some authors to have a closer relationship to dipnoans than to any other sarcopterygian, is considered to be inadequately known at present for definite statements about its relationship.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051900406
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Paleozoic lungfishes - a review (1986)
    New York, NY : Wiley-Blackwell
    Journal of Morphology 190 (1986), S. 93-131 
    Details
    ISSN: 0362-2525
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Stratigraphical and paleoecological evidence indicates that lungfishes evolved in shallow marine conditions. Devonian genera had large gill chambers, and the details of bony supports of the gill arches of the Late Devonian Griphognathus whitei demonstrate that the arches were all functional. These data, together with an analysis of the body forms of the Devonian genera, indicate that they were dependent on gill (and possibly skin) respiration. The oldest known dipnoans, Uranolophus and Speonesydrion, are held to be representative to two lineages that can be recognized by their buccal and branchial features. One had a “rasping” dentition formed of denticles and marginal ridges that were continually shed and remodelled; the other had a “crushing” dentition characterized by the presence of variously modelled dentine masses that continued growth throughout the life of the animal. A list of buccal and branchial characters associated with these modes of feeding is presented. Because the relations of the Dipnoi have to be examined in terms of the features possessed by the group when it first appeared as a separate entity, the final part of the paper makes an attempt to define the primitive dipnoan morphotype. It is shown that many features taken to be diagnostic of the Dipnoi by some workers were not present in its early members; failure to recognize this fact has led to erroneous hypotheses about dipnoan-amphibian relations.
    Additional Material: 23 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/jmor.1051900409
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Transfer of nuclei from 8-cell stage mouse embryos following use of nocodazole to control the cell cycle (1994)
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 39 (1994), S. 147-152 
    Details
    ISSN: 1040-452X
    Keywords: Mitosis ; Synchronization ; Mice ; Blastomere ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Mouse 2-, 4-, 8-, and 16-cell embryos were exposed to nocodazole in M16 culture medium. The effect of different concentrations and exposure times on the efficiency of cell cycle synchronization and the development of the treated embyros after release from the drug was determined. The minimum effective concentration (95% of arrested nuclei) for 4-, 8-, and 16-cell embryos was 5μM nocodazole. The effect upon subsequent development of mouse embryos depended upon both the stage of development of the embryo at treatment (P 〈 0.001) and the length of exposure to nocodazole (P 〈 0.001). Exposure to any concentration of nocodazole within the range 2.5-10 μM for 12 hr caused a reduction in the proportion of embryos that formed blastocysts. As the period of exposure to 5μM nocodazole increased from 12 to 24 hr, the proportion of embryos developing to the blastocyst stage decreased. The lower proportion of embyros developing to the blastocyst stage and to term (P 〈 0.01) suggests that the more advanced stages were more susceptible to damage as a result of exposure to nocodazole. The rate of development of 4-cell embryos to blastocysts was not affected when an exposure time of 9 hr was used. Together these results show that it is possible to use nocodazole to arrest mouse embryonic cells in mitosis but that it is not appropriate to culture the embryos in the presence of this drug for prolonged periods. Individual blastomeres completed mitosis at 60-90 min and started DNA synthesis at 120-150 min after release from nocodazole. Nuclei from blastomeres thus synchronized were used to conduct studies on the effect of the cell cycle on nuclear transfer. A signficant effect was found. When nuclei from 8-cell embryos in G1 or S-phase were used as nuclei donors, development to blastocyst was respectively 27% and none. ©Wiley-Liss, Inc.
    Additional Material: 6 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrd.1080390205
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    facet.materialart.
    Unknown
    Seeking Signs of Life on Mars: the Importance of Sedimentary Suites as Part of a Mars Sample Return Campaign (2018)
    In:  CASI
    Details
    Publication Date: 2019-07-13
    Description: Seeking the signs of life on Mars is often considered the "first among equal" objectives for any potential Mars Sample Return (MSR) campaign. Among the geological settings considered to have the greatest potential for recording evidence of ancient life or its pre-biotic chemistry on Mars are lacustrine (and marine, if ever present) sedimentary depositional environments. This potential, and the possibility of returning samples that could meaningfully address this objective, have been greatly enhanced by investigations of an ancient redox stratified lake system in Gale crater by the Curiosity rover.
    Keywords: Space Sciences (General)
    Type: JSC-E-DAA-TN52615 , International Mars Sample Return Conference; Apr 25, 2018 - Apr 27, 2018; Berlin; Germany
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...