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  • Adrenergic receptors  (2)
  • Biochemistry and Biotechnology  (2)
  • acid deposition  (2)
  • 1
    Electronic Resource
    Electronic Resource
    Stemflow nutrient inputs to soil in a successional hardwood forest (1992)
    Springer
    Plant and soil 140 (1992), S. 249-254 
    Details
    ISSN: 1573-5036
    Keywords: acid deposition ; hardwood forests ; nutrient leaching ; soil inputs ; stemflow ; succession
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Stemflow and throughfall from a regenerating (8-year-old) southern Appalachian hardwood forest were collected to examine the relative importance of tree bole nutrient leaching in response to acid deposition. Samples from nine (2 m2) stemflow collection plots were analyzed for four dormant season and 11 growing season rainstorm events. Results showed that, relative to throughfall fluxes, stemflow accounted, on average, for approximately 8.5% of total water reaching the forest floor during both dormant and growing season storms. Relative to foliar leaching, K-, SO4-, and PO4 ions appear to be the most easily leached ions from young tree stems. Proportional nitrate and base cation stemflow fluxes increased significantly (p〈0.05) with growing-season storm-event duration, suggesting that the stemsurface nutrient pool is depleted by precipitation more slowly than the foliar pool. On average, proportional stemflow fluxes of SO4 (12%) and K (14%) were consistently higher than reported maximum values for more mature forest stands, which indicates that small-scale stemflow inputs of ions such as these to the forest floor may be important in early successional ecosystems.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00010601
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Forest vegetation in relation to surface water chemistry in the North Branch of the Moose River, Adirondack Park, N.Y. (1987)
    Springer
    Biogeochemistry 3 (1987), S. 121-128 
    Details
    ISSN: 1573-515X
    Keywords: acid deposition ; forest cover ; forest structure ; biogeochemistry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Geosciences
    Notes: Abstract The Regional Integrated Lake-Watershed Acidification Study (RILWAS) was conducted to identify and to quantify the environmental factors controlling surface water chemistry in forested watersheds of the Adirondack region of New York. The RILWAS vegetation research was designed to: (1) compare the quantitative patterns of forest cover and tree community structure in the study catchments of the Moose River drainage system; and (2) identify important vegetation differences among study watersheds that might help to explain inter-watershed differences in water chemistry and aquatic responses to acidic deposition. Field transect data indicated that the overall drainage system includes 50% mixed forest cover, 38% hardwood forest, 10% coniferous forest, and 2% wetland cover. Major tree species include yellow birch, red spruce, American beech, sugar maple, eastern hemlock, and red maple. Analysis of forest structure indicated that mean weighted basal area estimates ranged two-fold from 24–48 m2ha−1 among watersheds. Likewise, mean weighted estimates for aboveground biomass and aboveground annual productivity ranged among watersheds from 160 to 320 MT ha−1 and from 8 to 18 MT ha−1 yr−1, respectively. Results showed that differences in surface water chemistry were independent of vegetation differences among watersheds.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02185188
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Spectral analysis of heart rate variability in the sepsis syndrome (1993)
    Springer
    Clinical autonomic research 3 (1993), S. 5-13 
    Details
    ISSN: 1619-1560
    Keywords: Sepsis syndrome ; Intensive care ; Heart rate variability ; Spectral analysis ; Respiration ; Autonomic nervous system ; Adrenergic receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Sympathetic and parasympathetic activity was evaluated on 39 occasions in 17 patients with the sepsis syndrome, by measurement of the variation in resting heart rate using frequency spectrum analysis. Heart rate was recorded by electrocardiography and respiratory rate by impedance plethysmography. The sepsis syndrome was established on the basis of established clinical and physiological criteria. Subjects were studied, whenever possible, during the period of sepsis and during recovery. Spectral density of the beat-to-beat heart rate was measured within the low frequency band 0.04 to 0.10 Hz (low frequency power, LFP) modulated by sympathetic and parasympathetic activity, and within a 0.12 Hz band width at the respiratory frequency mode (respiratory frequency power, RFP) modulated by parasympathetic activity. Results were expressed as the total variability (total area beneath the power spectrum), as the spectral components normalized to the total power (LFPn, RFPn) or as the ratio of LFP/RFP. During the sepsis syndrome, total heart rate variability and the sympathetically mediated component, LFPn were significantly lower than during the following recovery phase (ANOVA,p 〈 0.0001,p 〈 0.01 respectively). Both APACHE II (Acute Physiological and Chronic Health Evaluation) and TISS (Therapeutic Intervention Scoring System) scores showed an inverse correlation with total heart rate variability, logLFP, LFPn and the LFP/RFP ratio (p 〈 0.002 to 0.0001). Sympathetically mediated heart rate variability was significantly lower during the sepsis syndrome and was inversely proportional to disease severity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01819137
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    Paper (German National Licenses)
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  • 4
    Electronic Resource
    Electronic Resource
    Spectral analysis of heart rate variability in bronchial asthma (1992)
    Springer
    Clinical autonomic research 2 (1992), S. 105-111 
    Details
    ISSN: 1619-1560
    Keywords: Asthma ; Heart rate variability ; Spectral analysis ; Respiration ; Autonomic nervous system ; Adrenergic receptors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Sympathetic and parasympathetic activity was evaluated in ten healthy controls, nine asymptomatic, untreated asthmatic subjects and ten asthmatic patients during treatment for acute asthma, by measurement of the variation in resting heart rate using frequency spectrum analysis. Heart rate was recorded by ECG and respiratory rate by impedance plethysmography. Spectral density of the beat-to-beat heart rate was measured within the low frequency band 0.04 to 0.10 Hz (low frequency power) modulated by sympathetic and parasympathetic activity, and within a 0.12 Hz band width at the respiratory frequency mode (respiratory frequency power) modulated by parasympathetic activity. Acute asthmatics had higher heart rates than either of the other two groups; this was probably related to the effects of beta-adrenoceptor agonist medication. Sympathetically mediated heart rate variability (normalized low frequency power) was significantly lower in both asymptomatic (p 〈 0.002) and acute (p 〈 0.02) asthma subjects compared to controls. This is consistent with altered sympathetic/parasympathetic regulation of heart rate in subjects with bronchial asthma.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01819665
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    Paper (German National Licenses)
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  • 5
    Electronic Resource
    Electronic Resource
    Characterization of an oligonucleotide-binding fluorescent ligand for application in affinity purification of dsDNA (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 48 (1995), S. 25-35 
    Details
    ISSN: 0006-3592
    Keywords: DNA purification ; DNA-binding fluorophore ; Fluorescent ligand ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The fluorescent probe PO-PRO-3 was investigated as a potential ligand for the affinity immobilization and purification of genomic or plasmid DNA fragments. Affinities and mechanisms for PO-PRO-3 binding to superhelical and linearized pUC 18 plasmid DNA were examined through measurement of binding isotherms, continuous-variation analysis, and DNA titrations. In addition, the effects of DNA conformation, protein and RNA contaminants, solvent polarity, and ionic strength are examined with the aim of optimizing binding and elution conditions and of assisgning limits to the range of applicability of the affinity purification. © 1995 John Wiley & Sons, Inc.
    Additional Material: 11 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bit.260480106
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    Paper (German National Licenses)
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  • 6
    Electronic Resource
    Electronic Resource
    Multinuclear NMR study of enzyme hydration in an organic solvent (1998)
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 57 (1998), S. 686-693 
    Details
    ISSN: 0006-3592
    Keywords: NMR spectroscopy ; enzyme hydration ; organic solvents ; subtilisin ; Chemistry ; Biochemistry and Biotechnology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Multinuclear NMR spectroscopy has been used to study water bound to subtilisin Carlsberg suspended in tetrahydrofuran (THF), with the water itself employed as a probe of the hydration layer's physicochemical and dynamic characteristics. The presence of the enzyme did not affect the intensity, chemical shift or linewidth of water (up to 8% v/v) added to THF, as measured by 17O- and 2H-NMR. This finding suggests that hydration of subtilisin can be described by a three-state model that includes tightly bound, loosely bound, and free water. Solid-state 2H-NMR spectra of enzyme-bound D2O support the existence of a non-exchanging population of tightly bound water. An important implication is that the loosely-bound water is the same as free water from an NMR viewpoint. This loosely bound water must also be the water responsible for the large increase in catalytic activity observed in previous hydration studies. © 1998 John Wiley & Sons, Inc. Biotechnol Bioeng 57: 686-693, 1998
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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    Paper (German National Licenses)
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