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  • 11
    Electronic Resource
    Electronic Resource
    Springer
    Sexual plant reproduction 8 (1995), S. 231-241 
    ISSN: 1432-2145
    Keywords: Conditional male fertility ; Flavonols ; Maize ; Petunia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract This study compares conditional male fertility (CMF) in maize and petunia. CMF is a reversible defect in pollen germination or tube growth; pollen is nonfunctional in self-crosses but fully functional in outcrosses or when supplied with specific flavonol aglycones at pollination. CMF occurs in maize and petunia mutants that lack chalcone synthase (CHS) activity and therefore do not synthesize flavonols. In maize CMF seedlings and developing male florets, CHS transcripts accumulate to high levels, yet western blot analysis using an anti-CHS antiserum does not detect any CHS protein. This is in contrast to CMF petunia, where no CHS RNA is detected (Vogt et al. 1994). While CMF petunia pollen requires flavonols to germinate, CMF maize pollen germinates and grows both in vivo and in vitro without the addition of flavonols. However, pollen tubes abort after 12 h of growth which explains the lack of seed set in self crosses (Mo et al. 1992). Pollen tubes of CMF maize have an unusual morphology in vivo, with heavy callose deposits throughout the tube and tips that burst within the silk. Normal tube morphology and seed set are restored by adding flavonols to the silks at pollination. As previously shown with petunia, fecundity (seed set) may be enhanced in maize by adding quercetin and kaempferol at pollination.
    Type of Medium: Electronic Resource
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  • 12
    ISSN: 1432-1041
    Keywords: Key words Repaglinide ; Insulin secretagogue ; Type-2 diabetes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Abstract Objective: The present study was designed to assess the disposition of 14C-repaglinide in whole blood, plasma, urine and faeces, and to measure the total recovery of drug-related material in urine and faeces after a single 2-mg oral dose of 14C-repaglinide during multiple dosing. Methods: In this single-centre, open-label, phase-I trial, six healthy male volunteers received 2 mg of the prandial glucose regulator, repaglinide, four times daily for 13 days, 15 min before meals. On the morning of day 7, breakfast was omitted and the dose was given as an oral solution containing 2 mg of 14C-repaglinide. Results: After oral dosing, a mean peak plasma concentration of repaglinide of 27.74 ng · ml−1 (range: 16.84–36.65 ng · ml−1) was observed with a time to peak concentration of 0.5 h. Approximately 20% of repaglinide and its associated metabolites were distributed into red blood cells. No measurable 14C-radioactivity was present in whole blood samples 6 h after dosing. Within 96 h of dosing with 14C-repaglinide, 90% of the administered dose appeared in the faeces and 8% was excreted in urine. In the plasma, the major compound was repaglinide (61%). In the urine, the major metabolites were unidentified polar compounds, the aromatic amine (M1) (24%), and the dicarboxylic acid (M2) (22%). In the faeces, the major metabolite was M2 (66% of administered dose). Therefore, repaglinide was excreted predominantly as metabolites and the major in vivo metabolite of repaglinide in humans was M2. During regular dosing for 6 days, the morning plasma trough levels of repaglinide were, with very few exceptions, almost always too low to measure, indicating the absence of accumulation at this dose of 2 mg four times daily. Repaglinide was well tolerated, and there were no episodes of hypoglycaemia. Conclusion: After oral dosing with repaglinide, the mean peak plasma concentration was rapidly attained and, thereafter, plasma concentrations decreased promptly. The major route of excretion was via the faeces. These properties make repaglinide a suitable insulin secretagogue for all patients with type-2 diabetes who retain sufficient β-cell function.
    Type of Medium: Electronic Resource
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  • 13
    Electronic Resource
    Electronic Resource
    Springer
    Medical microbiology and immunology 123 (1941), S. 486-493 
    ISSN: 1432-1831
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Zusammenfassung Es wurde versucht, durch einige genau analysierte Beispiele hinzuweisen: 1. auf die krankmachende Bedeutung einiger Arzneimittelantigene, die sonst im allgemeinen gut vertragen werden und darum als „unschädlich” gelten, 2. auf die Bedeutung der „Herdreaktion” bei den allergischen Erkrankungen, d. h. auf die Tatsache, daß bei oberflächlichem Antigenkontakt neben der Kontaktstelle selbst („örtliche Reaktion”) oft auch das fernabgelegene, individuellprädisponierte allergische Reaktionsorgan spezifisch anspricht („Herdreaktion”).
    Type of Medium: Electronic Resource
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  • 14
    Electronic Resource
    Electronic Resource
    Springer
    Water, air & soil pollution 85 (1995), S. 1593-1598 
    ISSN: 1573-2932
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Throughfall was studied in three even-aged sitka spruce stands in Denmark during the years 1989 to 1994. Deposition of sea salts dominated the fluxes of substances in varying degrees between years and sites. During the study period, non-marine S deposition did not change substantially. At the site most affected by animal husbandry, fluxes of NH4 + and NO3 − increased over the years. Elevated fluxes of TOC, K+, and PO4 3− occurred in the growing season due to canopy leaching caused by attacks by the green spruce aphid. Fluxes of Cl−, SO4 2−, Na+, Ca2+, and Mg2+ were highest in the dormant season. Buffering of. pH was affected by the nitrogen dynamics in the canopy, and also, at least during the summer, by elevated levels of organic compounds.
    Type of Medium: Electronic Resource
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  • 15
    Electronic Resource
    Electronic Resource
    Springer
    Water, air & soil pollution 85 (1995), S. 2259-2264 
    ISSN: 1573-2932
    Source: Springer Online Journal Archives 1860-2000
    Topics: Energy, Environment Protection, Nuclear Power Engineering
    Notes: Abstract Canopy throughfall was collected in funnels equipped with tipping buckets. The funnels were installed at 4 distances from the tree trunk and at 6 depths in the canopy of a Norway spruce forest at Klosterhede, Denmark. The throughfall water flux was registered during individual rain events. The smallest quantity of throughfall was sampled closest to the tree trunk, and the largest quantity of throughfall was sampled in the periphery of the canopy at all levels in the canopy. The quantity of throughfall was highest at the top of the tree and decreased down through the canopy. The intensity of the water flow decreased through the canopy which brought the throughfall water in contact with the foliage for longer periods in the lower canopy than in the upper canopy. The higher wettability caused a larger leaching of especially potassium in the lower canopy. Differences in rain intensity did not influence the distribution and the pattern of water flow in the canopy.
    Type of Medium: Electronic Resource
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  • 16
    ISSN: 1432-2242
    Keywords: Brassicaceae ; Interspecific hybridization ; Synteny groups ; Risk assessment
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract We have examined the inheritance of 20 rapeseed (Brassica napus)-specific RAPD (randomly amplified polymorphic DNA) markers from transgenic, herbicide-tolerant rapeseed in 54 plants of the BC1 generation from the cross B. junceax(B. junceaxB. napus). Hybridization between B. juncea and B. napus, with B. juncea as the female parent, was successful both in controlled crosses and spontaneously in the field. The controlled backcrossing of selected hybrids to B. juncea, again with B. juncea as the female parent, also resulted in many seeds. The BC1 plants contained from 0 to 20 of the rapeseed RAPD markers, and the frequency of inheritance of individual RAPD markers ranged from 19% to 93%. The transgene was found in 52% of the plants analyzed. Five synteny groups of RAPD markers were identified. In the hybrids pollen fertility was 0–28%. The hybrids with the highest pollen fertility were selected as male parents for backcrossing, and pollen fertility in the BC1 plants was improved (24–90%) compared to that of the hybrids.
    Type of Medium: Electronic Resource
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  • 17
    Electronic Resource
    Electronic Resource
    Springer
    International journal of technology and design education 5 (1995), S. 35-50 
    ISSN: 1573-1804
    Keywords: Bildung ; concept mapping ; technology education
    Source: Springer Online Journal Archives 1860-2000
    Topics: Art History , Education , Technology
    Notes: Abstract Reflection has become a buzzword in the educational profession. Its meaning, however, frequently remains vague. In this paper the meaning of reflection for technology education is elaborated on three levels. The first is a philosophical and educational level. The idea of ‘Bildung’, conceived as the formation of an autonomous personality, becomes a central category for instruction about technology. The second level is the realm of curriculum development and teachers' planning. The reference to Bildung implies that technology education should be based on ‘technological key problems’ that apply to all members of society. On the third level, the meaning of reflection will be elaborated in the context of a qualitative research approach on teacher thinking in technology education. It resorts to the categories of the curriculum model and is illustrated by a case study on teacher planning in computer education.
    Type of Medium: Electronic Resource
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  • 18
    ISSN: 1573-5036
    Keywords: drought ; irrigation ; fertilizer application ; nutrients ; Picea abies ; tree growth
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract Water and nutrient supply to forest trees are major factors controlling tree growth and forest vitality. Therefore, changes in the supply of water and nutrients to the trees may be important contributing reasons to the forest damages observed in Europe. Such changes may be caused by several factors, e.g. air pollution, soil acidification and climate change. The present study investigates possible effects on tree growth, growth related parameters and nutrition related to changes in the water and nutrient supply. Water and nutrient supply to the forest soil was manipulated in three roof covered plots. The treatments consisted of 1) summer drought, 2) irrigation and 3) combined irrigation and fertilizer application (fertigation). The results from the roof covered treatment plots were compared to a control plot without roof. Increased supply of water during the spring and early summer increased the diameter growth, whereas application of nutrients in addition to irrigation had no additional effect on tree growth. Addition of nutrients increased the needle content of P, Mn, Ca and Mg. Extended summer drought for 2 months had no effect on the tree growth or other growth parameters, but drought reduced the root development in the upper soil layer. Furthermore, drought induced significant stress symptoms by increasing the cone shredding substantially.
    Type of Medium: Electronic Resource
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  • 19
    ISSN: 1573-5036
    Keywords: atmospheric deposition ; biogeochemical cycling ; decomposition ; experimental manipulations ; soil water chemistry ; throughfall
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Abstract At Klosterhede, Denmark experimental manipulations of the input of water and nutrients to a Norway spruce forest stand have been performed. The manipulations included fertilizer application, irrigation and creation of artificial dry periods. Further, the acidic input was excluded from the soil by a 1200 m2 roof. The aim of this study was to quantify the effects of air pollutants on the internal cycling of nutrients in the forest ecosystem and to assess the influence of the manipulations on the canopy interacting processes, the soil water composition and the turnover of organic matter. The improved nutrient availability and the increased soil water content in the fertigation (fertilizer application + irrigation) and the irrigation plots under the roof resulted in an increased decomposition of cotton strips compared to the uncovered control plot. However, the decomposition of needle material (litterbags) in the roof covered plots was reduced probably due to altered humidity conditions in the humic layer as a result of the irrigation system. Significant changes to the manipulations were seen in the soil water concentrations of SO4 2- in the irrigated and the fertigated plots and of K+ in the irrigated plot which show that the internal cycling and dynamics of sulphur and potassium are very sensitive to interference in the input. The effect of reduced acid input on soil water concentrations of Al and H+ was not evident before the 5th year of treatment where Al concentration was reduced almost 50% at 55 cm depth on the “clean rain” (irrigated) plot. It was not possible to detect any enlarged throughfall deposition on the fertigated and irrigated plots despite an observed rise in the canopy surface area on these plots or to detect any changes in canopy leaching reflecting changes in nutrient status.
    Type of Medium: Electronic Resource
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  • 20
    Electronic Resource
    Electronic Resource
    Springer
    Biotechnology techniques 10 (1996), S. 485-490 
    ISSN: 1573-6784
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary A sampling system which enables on-line measurements of the precursor phenoxyacetic acid (POAA) in penicillin fermentation by membrane inlet mass spectrometry is presented and its capacity for feed-back regulation of POAA to a low predefined concentration in a penicillin-V fermentation over 150 hours is demonstrated. The system measures alternately filtered sample and standard solution in a measuring cycle which is shorter than the response time of membrane inlet mass spectrometry (MIMS) but sufficiently long to decide whether the concentration of POAA in the sample is higher or lower than in the standard solution at set point concentration. The decision is used for on-off regulation of the addition of POAA.
    Type of Medium: Electronic Resource
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