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
Filter
  • Polymer and Materials Science  (7)
  • Aortic baroreceptor afferents  (1)
  • Ash-free biomass  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Earthworm response to rotation and tillage in a Missouri claypan soil (1999)
    Springer
    Biology and fertility of soils 29 (1999), S. 343-347 
    Details
    ISSN: 1432-0789
    Keywords: Key words Aporrectodea trapezoides ; Diplocardia singularis ; Population density ; Ash-free biomass ; Crop rotation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract  Agricultural management practices affect earthworm populations. A field experiment was conducted to determine the effect of two rotations and two tillage systems on earthworm population density and biomass in a claypan soil. The rotations were soybean/corn and wheat/corn, and the tillage systems were conventional tillage (chisel plowed and disked) and no-tillage. Earthworm and soil samples were collected in fall 1995, spring 1996, and fall 1996. Aporrectodea trapezoides and Diplocardia singularis were the species identified at the site. A. trapezoides accounted for 92–96% of the total earthworm population density and D. singularis accounted for only 4–8%. In a no-till system, soybean/corn rotation resulted in significantly greater population density of A. trapezoides compared with the wheat/corn rotation. Crop residue quality (low C:N ratio) and quantity were important factors in increasing A. trapezoides population density and biomass. Conventional tillage markedly decreased population density and biomass of both earthworm species. Our results suggest that rotation and tillage significantly affect earthworm population density and biomass.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003740050563
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Presynaptic depolarization in myelinated vagal afferent fibres terminating in the nucleus of the tractus solitarius in the cat (1986)
    Springer
    Pflügers Archiv 406 (1986), S. 12-19 
    Details
    ISSN: 1432-2013
    Keywords: Slowly adapting lung stretch receptor afferents ; Aortic baroreceptor afferents ; Presynaptic depolarization ; Neural control of respiration ; Neural control of circulation ; Nuclei of the solitary tract
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The presynaptic influences that act on terminals of slowly adapting lung stretch receptor afferents and aortic baroreceptor afferents within the nucleus of the solitary tract were assessed using intracellular recording and antidromic stimulation techniques. Central respiratory influences on the axcitability of lung stretch receptor terminals were observed in 29% (4 of 14) of measurements. These were confirmed in intracellular recordings where membrane depolarizations in synchrony with phrenic nerve discharge were seen in 17% (4 of 24) of fibres. In three cases membrane depolarization also occurred synchronously with artificial lung inflation. Neither tests of excitability nor intracellular recording revealed any evidence for equivalent presynaptic influences on 16 myelinated aortic baroreceptor terminals. Stimulation of the superior laryngeal nerve evoked depolarizations in 50% (7 of 14) of lung stretch receptor terminals. These took the form of complex waves of depolarization with both short (3–8 ms) and long latency (27–35 ms) components. The amplitude of the long latency response increased during the period of phrenic nerve discharge, i.e. during “central inspiration”. These effects are discussed in relation to the central respiratory influences on both respiratory and cardiovascular reflexes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00582946
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The kinetics of the renaturation of deoxyribonucleic acid denatured in the presence of copper (II) ions (1972)
    New York : Wiley-Blackwell
    Biopolymers 11 (1972), S. 1661-1684 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: DNA which has been heat denatured in the presence of Cu++ ions can be completely and rapidly renatured by increasing the ionic strength of the solution above a critical value. A kinetic study of this renaturation recation was carried out by following the associated UV absorbance change and also by following the change in free Cu++ ion concentration by means of a specific Cu++ ion activity electrode. The data obtained could be fitted to first-order kinetics for a considerable extent of the reaction and the rate constant was found to increase with temperature and ionic strength, but to decrease markedly as the bulk viscosity of the solution was increased. At temperatures greater than 5°C the reaction rate depended on the time elapsing between denaturation and the commencement of the renaturation reaction. As there was good agreement between the rate constants obtained by following the decrease in hyperchromism and by following the increase in free Cu++ ion concentration, it is concluded that under the conditions employed, the rate of renaturation is determined by the rate of release of Cu++ ions from the denatured DNA-Cu++ complex.
    Additional Material: 14 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1972.360110812
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Interaction of proflavine and 9-aminoacridine with DNA at temperatures below and above the melting temperature (1971)
    New York : Wiley-Blackwell
    Biopolymers 10 (1971), S. 399-410 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The influence of temperature on the binding of 9-aminoacridine and of proflavine to E. coli DNA in 10-3M NaCl solution has been determined by a spectrophotometric technique. The inadequacy of the expression normally used for the determination of the extent of binding is discussed with reference to measurements at temperatures above which dissociation of the double helix occurs. A method of determining the relative extents of binding to native and denatured DNA at elevated temperatures is described.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.360100214
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The sedimentation and diffusion of sodium polymethacrylate and polymethacrylic acid (1954)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 12 (1954), S. 209-219 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The sedimentation constants and diffusion coefficients of sodium polymethacrylate and of polymethacrylic acid have been determined at various concentrations of polymer and of added electrolyte and the nature of the charge effects is considered. A ratio y = (molarity of added electrolyte)/(grundmolarity of polymer) is used to obtain S20 at y = ∞ when the polyelectrolyte is assumed to be uncharged. The variation of the effective radius with y is considered not to be due to asymmetry but to the open network nature of the polyelectrolyte coil.The sedimentation constant of unionized polymethacrylic acid is determined and also the variation of sedimentation constant with degree of ionization.
    Additional Material: 10 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1954.120120117
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Hydrodynamic properties of polyelectrolytes. Part II. Poly-4-vinylpyridine (1956)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 21 (1956), S. 473-482 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The hydrodynamic properties of fractionated samples of poly-4-vinylpyridine have been studied. The intrinsic viscosities and the Huggins' constant (k′) have been obtained. The effect of shear on the viscosity disappears at high dilution. The sedimentation constants (S0) have been measured, and the streaming birefringence has been investigated at various concentrations and shear gradients. The Peterlin theory for concentrated solutions is in good agreement with the results for the orientation angle, but is not so well in accord with the magnitude of the birefringence. The partial specific volume is low (0.685). Molecular weights have been calculated for the fractions, and it is concluded that the shape of the molecules in solution approximates to that of a stiff coil.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1956.120219911
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Hydrodynamic properties of polyelectrolytes. Part I. Poly-4-vinyl-N-n-butylpyridinium bromide (1956)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 21 (1956), S. 463-472 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The viscosity, streaming birefringence, and sedimentation of a sample of poly-4-vinyl-N-n-butylpyridinium bromide have been measured in aqueous and in sodium chloride solutions. The theory of Peterlin for concentrated solutions has been found to be in agreement with the results. Values of the molecular weight have been calculated by different methods and a value of 9 × 105 has been chosen.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1956.120219910
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Solution viscosity and molecular weight of polystyrene prepared by aluminium chloride catalysis (1952)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Polymer Science 9 (1952), S. 286-288 
    Details
    ISSN: 0022-3832
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1952.120090312
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Concentration dependence of the reduced viscosity of dilute aqueous polyelectrolyte solutions (1965)
    New York : Wiley-Blackwell
    Journal of Polymer Science Part A: General Papers 3 (1965), S. 1941-1948 
    Details
    ISSN: 0449-2951
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Physics
    Notes: The concentration dependence of the reduced viscosity has been studied for several polyelectrolytes in conductivity water. It is shown that the viscosity maximum previously reported for polyelectrolyte solutions without added electrolyte can be explained either by the presence of ionic impurities in the solvent or by the contamination of the solutions. It is concluded that the folding chain theory of polyelectrolyte solutions requires amendment to account for the experimental results on counterion association. A suggested amendment to the theory implies that the application of the Huggins equation to the concentration dependence of polyelectrolyte solutions in the presence of added electrolyte may not lead to information concerning the interactions between the polyions in solution.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/pol.1965.100030523
    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...