Library

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
    Electronic Resource
    Electronic Resource
    Combined laser and atomic force microscope lithography on aluminum: Mask fabrication for nanoelectromechanical systems (1999)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 74 (1999), S. 3206-3208 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: A direct-write laser system and an atomic force microscope (AFM) are combined to modify thin layers of aluminum on an oxidized silicon substrate, in order to fabricate conducting and robust etch masks with submicron features. These masks are very well suited for the production of nanoelectromechanical systems (NEMS) by reactive ion etching. In particular, the laser-modified areas can be subsequently locally oxidized by AFM and the oxidized regions can be selectively removed by chemical etching. This provides a straightforward means to define the overall conducting structure of a device by laser writing, and to perform submicron modifications by AFM oxidation. The mask fabrication for a nanoscale suspended resonator bridge is used to illustrate the advantages of this combined technique for NEMS. © 1999 American Institute of Physics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.124106
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Uptake and Distribution of Radioactive Carbon from Labelled Substrates by Various Cellular Components of Spinaeb Leaves (1959)
    Oxford, UK : Blackwell Publishing Ltd
    Physiologia plantarum 12 (1959), S. 0 
    Details
    ISSN: 1399-3054
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1399-3054.1959.tb07970.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Spatial and temporal variability of phytoplankton biomass and taxonomic composition around Elephant Island, Antarctica, during the summers of 1990–1993 (1995)
    Springer
    Marine biology 123 (1995), S. 677-686 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract During the austral summers of 1990–1993, phytoplankton studies were conducted in the vicinity of Elephant Island, Antarctica, to investigate the spatial and temporal variability of phytoplankton biomass and taxonomic composition. There was much intraannual variability, with a trend for increasing biomass from January–February (Leg I) to February–March (Leg II), except in the 1993 studies. There was also a change in phytoplankton composition between the two legs. During 1990–1991 the increase was due mostly to diatoms, during 1992 mostly to an increase of flagellates; during 1993 there was a decrease in total biomass between the two legs, with diatoms decreasing, so that dinoflagellates, which increased slightly in numbers, dominated the biomass during the second leg. There was also much inter-annual variability, with the summers of 1990–1991 having greater biomass and higher proportions of microplanktonic diatoms than that of 1992–1993, which had a higher proportion of flagellates. Cluster analyses revealed the presence of four major phytoplankton assemblages, with varying geographical distributions. The northwestern portion of the grid (Drake Passage waters), was characterized by nanoplanktonic diatoms during 1990–1991 and 1993, but by nanoplanktonic flagellates during 1992. The central area (Drake-Bransfield confluence) was characterized by microplanktonic diatoms in 1990–1991, but by cryptophytes or flagellates in 1992–1993. The south and southeastern portion of the area (Bransfield Strait waters) was characterized mainly by either cryptophytes or other flagellates during all 4 yr. The spatial and temporal variability of phytoplankton could not be ascribed specifically to the geographical extent of the different water masses found in the study area, but appears to be due to changing growth conditions in the upper water column as influenced by physical mixing and meteorological conditions, as well as to effects of differential grazing.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00349110
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Effects of sea-ice extent and krill or salp dominance on the Antarctic food web (1997)
    [s.l.] : Macmillan Magazines Ltd.
    Nature 387 (1997), S. 897-900 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Krill (Euphausia superba) provide a direct link between primary producers and higher trophic levels in the Antarctic marine food web. The pelagic tunicate Salpa thompsoni can also be important during spring and summer through the formation of extensive and dense blooms. Although salps are not a ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/387897a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    A new glucose oxidase from Aspergillus niger: characterization and regulation studies of enzyme and gene (1996)
    Springer
    Applied microbiology and biotechnology 46 (1996), S. 371-381 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract  A new glucose oxidase from Aspergillus niger was isolated and characterized. The enzyme showed different kinetic and stability characteristics when compared to a commercially available batch of A. niger glucose oxidase. The gene encoding the new glucose oxidase was isolated and DNA sequence analysis of the coding region showed 80% identity to the sequence of a glucose oxidase gene previously published. However, the similarity of the non-coding sequences up- and downstream of the open reading frame was much less, showing only 66% and 50% identity respectively. Despite the low degree of similarity between the promotor region of the new gene and the previously published one, the new glucose oxidase was likewise induced by calcium carbonate. In addition, we showed that this induction occurred on the transcriptional level. Observations concerning the effect of gluconolactone and the levels of glucose-6-phosphate isomerase upon calcium carbonate induction suggested that the enhancement of glucose oxidase biosynthesis by calcium carbonate was accompanied by a metabolic shift from glycolysis to the pentose phosphate pathway.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166232
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    A new glucose oxidase from Aspergillus niger: characterization and regulation studies of enzyme and gene (1996)
    Springer
    Applied microbiology and biotechnology 46 (1996), S. 371-381 
    Details
    ISSN: 1432-0614
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Abstract A new glucose oxidase from Aspergillus niger was isolated and characterized. The enzyme showed different kinetic and stability characteristics when compared to a commercially available batch of A. niger glucose oxidase. The gene encoding the new glucose oxidase was isolated and DNA sequence analysis of the coding region showed 80% identity to the sequence of a glucose oxidase gene previously published. However, the similarity of the non-coding sequences up- and downstream of the open reading frame was much less, showing only 66% and 50% identity respectively. Despite the low degree of similarity between the promotor region of the new gene and the previously published one, the new glucose oxidase was likewise induced by calcium carbonate. In addition, we showed that this induction occurred on the transcriptional level. Observations concerning the effect of gluconolactone and the levels of glucose-6-phosphate isomerase upon calcium carbonate induction suggested that the enhancement of glucose oxidase biosynthesis by calcium carbonate was accompanied by a metabolic shift from glycolysis to the pentose phosphate pathway.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00166232
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Aluminum Concentrations in Selected Foods Prepared in Aluminum Cookware, and Its Implications for Human Health (1997)
    Springer
    Bulletin of environmental contamination and toxicology 58 (1997), S. 1 -7 
    Details
    ISSN: 1432-0800
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering , Medicine
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001289900292
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Distribution of phytoplankton and nutrients in relation to different water masses in the area around Elephant Island, Antarctica (1997)
    Springer
    Polar biology 18 (1997), S. 145-153 
    Details
    ISSN: 1432-2056
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract During January March 1996 the U.S. Antarctic Marine Living Resources program carried out an extensive multidisciplinary study in a 40,000 km2 sampling grid around Elephant Island, Antarctica. The physical, chemical, optical, and biological characteristics of the upper water column (0–750 m) were determined at 91 hydrographic stations. Analysis of the temperature and salinity data showed that six different hydrographic zones could be differentiated. The biological (phytoplankton distribution and abundance) and chemical (inorganic nutrient concentrations) data also showed characteristic differences within each of these six zones. In spite of high concentrations of inorganic N, P, and Si in all six zones, all stations in the northwest portion of the sampling grid (Drake Passage waters) showed very low chlorophyll-a concentrations in surface waters and a sub-surface maximum at increased depth. As stations in this zone have a relatively stable upper mixed layer of 40 m, excess macro-nutrients, and adequate solar radiation for maximal photosynthetic rates, this suggests that rates of primary production in this zone are limited by a micro-nutrient such as Fe. Phytoplankton abundance was much greater in the Bransfield Strait, in waters influenced by Bellingshausen Sea Water, and in the frontal zones where these water masses mix with Drake Passage waters. Relatively low and deeply distributed phytoplankton abundance was found at all stations in the southeastern portion of our sampling grid, where the upper water column was very weakly stratified and showed the characteristics of Weddell Sea water. The areas of enhanced phytoplankton biomass in the AMLR sampling grid roughly correspond to the areas where krill are generally also found in greater abundance. The overall biological productivity of the Elephant Island region would thus appear to be dependent upon the circulation patterns of the major water masses that intrude into this area.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003000050169
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Heterogeneity of Na+/K+-ATPase from rectal gland of Squalus acanthias is not due to α isoform diversity (1999)
    Springer
    Pflügers Archiv 437 (1999), S. 517-522 
    Details
    ISSN: 1432-2013
    Keywords: Key words Electronic autoradiography ; Enzyme heterogeneity ; α Isoforms ; Isoform-specific antibodies ; Na+/K+-ATPase ; [3H]Ouabain binding ; Shark rectal gland ; Squalus acanthias
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Purified Na+/K+-ATPase (EC 3.6.1.37) isolated from the rectal gland of Squalus acanthias was characterized in ouabain-binding studies and with respect to isoform(s) of the α peptide. To avoid enzyme inactivation [3H]ouabain equilibrium binding was carried out at 20°C. The heterogeneity of Na+/K+-ATPase isolated from shark rectal gland was similar in [3H]ouabain binding as previously seen in hydrolytic studies. The binding isotherms were compatible with the existence of a high-affinity (K dis 0.69 nM) and a low-affinity (K dis 42 nM) component of 1.46 and 0.79 nmol.(mg protein)–1, respectively. In Western blots the α peptide of the enzyme hybridized with an isoform-specific polyclonal antibody raised to an α3-specific region of the large intracellular domain of rat Na+/K+-ATPase, but not with the supposed α3-specific monoclonal antibody MA3-915 with its epitope near the N-terminus. Semi-quantitative analysis of the reaction of the α3-specific polyclonal antibody with the α peptide from the shark enzyme compared to the reaction with α peptide from rat brain enzyme indicated that this region is not exactly the same in the two species. The α peptide of shark enzyme was not recognized by α1- or α2-specific polyclonal antibodies, or by the α1-specific monoclonal antibodies 3B and F6. The large intracellular domain of Na+/K+-ATPase from shark rectal gland thus seems to be α3-like and no α isoform heterogeneity seems able to account for the heterogeneity seen in ouabain binding.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00008089
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The determination of the age and growth of SE Asian mangrove seedlings from internodal counts (1999)
    Springer
    Mangroves and salt marshes 3 (1999), S. 251-257 
    Details
    ISSN: 1572-977X
    Keywords: Avicennia alba ; growth ; internodal sequences ; mangrove age determination ; Rhizophora apiculata ; Sonneratia caseolaris ; Thailand
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The occurrence of periodic changes in the length of the internodes of the seedlings of SE Asian mangrove species (Rhizophora apiculata, Avicennia alba, and Sonneratia caseolaris) growing in the Pak Phanang estuary (Nakhon Si Thammarat, SE Thailand) was confirmed. The annual nature of these periodic changes was verified through comparisons with the observed average number of internodes produced by plants tagged for one year. The cycles in the sequence of internodal length of the seedlings had an average (± SE) period of 16.0 ± 0.78 internodes for Avicennia alba, 25.0 ± 1.2 internodes for Sonneratia caseolaris, and 8.29 ± 0.40 internodes for Rhizophora apiculata. These values are remarkably close to, and not significantly different (t‐test, P 〉 0.05) from the average (± SE) annual number of internodes of 17.6 ± 0.8 for Avicennia alba, 28.8 ± 2.1 for Sonneratia caseolaris, and 8.03 ± 0.36 for Rhizophora apiculata produced in a year by tagged plants. In addition, the average (± SE) growth of the tagged plants was 0.39 ± 0.018 cm day-1 for Avicennia alba, 0.24 ± 0.015 cm day-1 for Sonneratia caseolaris, and 0.091 ± 0.0036 cm day-1 for Rhizophora apiculata. These estimates were very close to those (0.45 ± 0.06 cm day-1 for Avicennia alba, 0.32 ± 0.01 cm day-1 for Sonneratia caseolaris, and 0.13 ± 0.005 cm day-1 for Rhizophora apiculata) derived as the product of the mean number of internodes produced per day, calculated from the inferred number of internodes produced per year, and the mean length of the internodes of the plants. These findings indicate that the use of regular, annual changes in the length of the internodes of mangrove seedlings can be used reliably to determine their age and to estimate their growth rate.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1023/A:1009967401337
    Library Location Call Number Volume/Issue/Year 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...