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  • 1
    ISSN: 1432-184X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The microbial biomass and community structure of eight Chinese red soils with different fertility and land use history was investigated. Two community based microbiological measurements, namely, community level physiological profiling (CLPP) using Biolog sole C source utilization tests and phospholipid fatty acid (PLFA) profiles, were used to investigate the microbial ecology of these soils and to determine how land use alters microbial community structure. Microbial biomass-C and total PLFAs were closely correlated to organic carbon and total nitrogen, indicating that these soil microbial measures are potentially good indices of soil fertility in these highly weathered soils. Metabolic quotients and C source utilization were not correlated with organic carbon or microbial biomass. Multivariate analysis of sole carbon source utilization patterns and PLFAs demonstrated that land use history and plant cover type had a significant impact on microbial community structure. PLFAs showed these differences more than CLPP methods. Consequently, PLFA analysis was a better method for assessing broad-spectrum community differences and at the same time attempting to correlate changes with soil fertility. Soils from tea orchards were particularly distinctive in their CLPP. A modified CLPP method, using absorbance readings at 405 nm and different culture media at pH values of 4.7 and 7.0, showed that the discrimination obtained can be influenced by the culture conditions. This method was used to show that the distinctive microbial community structure in tea orchard soils was not, however, due to differences in pH alone.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 114 (2001), S. 3752-3764 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The energetics of Pb film grown at 300 K on two well-defined oxides [a MgO(100) thin film and a p(2×1)-oxide on Mo(100)] have been measured using single-crystal adsorption microcalorimetry. The evolution of the film morphology was followed using Auger electron spectroscopy (AES). An initial heat of adsorption of 103 kJ/mol is observed for the Pb/MgO(100) system. Auger results indicate that this is due to the formation of an ∼20 atom Pb island in the first pulse of Pb gas incident on the MgO(100) surface. This allows the extraction of a Pb–MgO(100) bond energy of ∼32±2 kJ/mol in the small two-dimensional particles formed in the first pulse. As more Pb is deposited onto the MgO(100) surface, the Pb forms three-dimensional islands. The integral of the heats of adsorption up to high coverage indicates an adhesion energy of 76.5±∼20 μJ/cm2 for large 3D Pb particles to the MgO(100) substrate. This indicates a Pb–MgO(100) bond energy of 49±13 kJ/mol at the 3D interface. Similar analyses of the Pb/p(2×1)-oxide on Mo(100) surface give an initial heat of adsorption of 146.2 kJ/mol and an adhesion energy of 82.5±20 μJ/cm2 for thick Pb films. This indicates a bond energy of 52±12 kJ/mol for a Pb atom to this surface at the interface of a thick Pb film. The metal's sticking probabilities as a function of coverage and the coverage-dependent changes in optical reflectivity were measured. For the Pb/MgO(100) system, an initial sticking probability of 0.70 at 300 K was observed, whereas for the Pb/p(2×1)-oxide on Mo(100) surface unit sticking probability was observed. The relationship between these quantities and the adsorption energetics is discussed. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Urethral epithelial cells are invaded by Neisseria gonorrhoeae during gonococcal infection in men. To understand further the mechanisms of gonococcal entry into host cells, we used the primary human urethral epithelial cells (PHUECs) tissue culture system recently developed by our laboratory. These studies showed that human asialoglycoprotein receptor (ASGP-R) and the terminal lactosamine of lacto-N-neotetraose-expressing gonococcal lipooligosaccharide (LOS) play an important role in invasion of PHUECs. Microscopy studies showed that ASGP-R traffics to the cell surface after gonococcal challenge. Co-localization of ASGP-R with gonococci was observed. As ASGP-R-mediated endocytosis is clathrin dependent, clathrin localization in PHUECs was examined after infection. Infected PHUECs showed increased clathrin recruitment and co-localization of clathrin and gonococci. Preincubating PHUECs in 0.3 M sucrose or monodansylcadaverine (MDC), which both inhibit clathrin-coated pit formation, resulted in decreased invasion. N. gonorrhoeae strain 1291 produces a single LOS glycoform that terminates with Gal(β1–4)GlcNac(β1–3)Gal(β1–4)Glc (lacto-N-neotetraose). Invasion assays showed that strain 1291 invades significantly more than four isogenic mutants expressing truncated LOS. Sialylation of strain 1291 LOS inhibited invasion significantly. Preincubation of PHUECs in asialofetuin (ASF), an ASGP-R ligand, significantly reduced invasion. A dose–response reduction in invasion was observed in PHUECs preincubated with increasing concentrations of NaOH-deacylated 1291 LOS. These studies indicated that an interaction between lacto-N-neotetraose-terminal LOS and ASGP-R allows gonococcal entry into PHUECs.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1365-2222
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background IL-18 is a cytokine which is known to have an important role in the development of a Th1 lymphocyte response. As such, it may have a regulatory role in asthma by modifying Th2 lymphocyte responses. Cigarette smoking may amplify the airway inflammation associated with asthma.Objective This study investigated if IL-18 could be detected in induced sputum from asthmatics and normal subjects and if smoking altered IL-18 levels.Methods Induced sputum was obtained from asthmatic (31 smokers, 35 non-smokers) and normal (20 smokers, 20 non-smokers) subjects. All smokers had a smoking history of 〈inlineGraphic alt="geqslant R: gt-or-equal, slanted" extraInfo="nonStandardEntity" href="urn:x-wiley:09547894:CEA1973:ges" location="ges.gif"/〉15 pack years. IL-18 levels in sputum supernatant were measured by ELISA. IL-18 mRNA expression and cellular localization were assessed by quantitative PCR and immunocytochemistry, respectively.Results Smoking was associated with a significant reduction in IL-18 levels (median (interquartile range) – smokers 20 (0–102) pg/mL vs. non-smokers 358 (50–876) pg/mL, P〈0.001). This was more pronounced in asthmatics (smokers, 47 (40–64) pg/mL vs. non-smokers, 530 (30–1484) pg/mL; P〈0.001) than in normal subjects (smokers, 25 (0–78) pg/mL vs. non-smokers, 247 (50–656) pg/mL; P〈0.01). Within each of the smoking and non-smoking groups there was no significant difference in IL-18 levels between asthmatic and normal subjects. There was no correlation between sputum IL-18 levels and any specific cell type in the sputum samples nor serum IgE levels. IL-18 mRNA expression was reduced in asthmatic smokers compared with non-smokers. IL-18 production was localized to sputum macrophages by immunocytochemistry.Conclusions IL-18 is detectable in induced sputum samples from both asthmatic and normal subjects. Cigarette smoking significantly reduces sputum IL-18 levels. This effect is more pronounced in asthmatics than in normal subjects.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    Philosophy 11 (1936), S. 98-102 
    ISSN: 0031-8191
    Source: Cambridge Journals Digital Archives
    Topics: Philosophy
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    Philosophy 10 (1935), S. 154-167 
    ISSN: 0031-8191
    Source: Cambridge Journals Digital Archives
    Topics: Philosophy
    Notes: The problem of suffering is essentially a problem in philosophical theology. For many philosophical systems the phenomena of suffering set no special problem at all. The most influential philosophies of the present age, for example, have almost nothing to say on the subject—and there is no reason why, on their metaphysical; principles, they should say anything. The problem is a relevant one only for those philosophies which claim to be in at least general accord with the “religious interpretation of the universe.” But for them it is crucial. Given a Weltanschauung like that of Absolute Idealism, for which the ultimate principle from which all things derive their being is an Infinite and Perfect Spirit, and it becomes at once a clear obligation to offer some explanation of how we are to reconcile the Goodness of God with the existence in the world of so much suffering which is prima facie just bad. As we all know, the problem is an extraordinarily hard one to solve. But, inasmuch as the religious interpretation of the universe demands its solution as a condition of its own possibility, its importance is proportionate to its difficulty.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    Philosophy 10 (1935), S. 107-108 
    ISSN: 0031-8191
    Source: Cambridge Journals Digital Archives
    Topics: Philosophy
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Cambridge : Cambridge University Press
    Philosophy 11 (1936), S. 239-240 
    ISSN: 0031-8191
    Source: Cambridge Journals Digital Archives
    Topics: Philosophy
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Plant, cell & environment 25 (2002), S. 0 
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Atmospheric [CO2] affects photosynthesis and therefore should affect the supply of carbon to roots. To evaluate interactions between carbon supply and nutrient acquisition, the [CO2] effects on root growth, proteoid root formation and phosphorus (P) uptake capacity were studied in white lupin (Lupinus albus L.) grown hydroponically at 200, 410 and 750 µmol mol−1 CO2, under sufficient (0·25 mm P) and deficient (0·69 µm P) phosphorus. Plant size increased with increasing [CO2] only at high P. Both P deficiency and increasing [CO2] increased the production of proteoid clusters; the increase in response to increased [CO2] was proportionally greater from low to ambient [CO2] than from ambient to high. The activity of phosphoenol pyruvate carboxylase in the proteoid root, the exudation of organic acids from the roots, and the specific uptake of P increased with P deficiency, but were unaffected by [CO2]. Increasing [CO2] from Pleistocene levels to those predicted for the next century increased plant size and allocation to proteoid roots, but did not change the specific P uptake capacity per unit root mass. Hence, rising [CO2] should promote nutrient uptake by allowing lupins to mine greater volumes of soil.
    Type of Medium: Electronic Resource
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