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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Accreditation and quality assurance 4 (1999), S. 3-13 
    ISSN: 1432-0517
    Keywords: Key words Metrology ; Primary methods ; Reference materials ; Traceability ; Isotope dilution mass spectrometry
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract  The UK Valid Analytical Measurement Programme has pump-primed developments in chemical metrology, through a major project on reference methodology and reference materials. This paper provides an overview of developments during 1994–1997 and covers work on primary methods for trace inorganic and trace organic analysis, including the use of isotope dilution mass spectrometry; studies of sample pre-treatment, including digestion, extraction, and separation aimed at improving this weak link in the traceability chain; prioritisation, production and marketing of both pure substance and matrix reference materials; and international collaboration concerned with interlaboratory comparisons and the development of concepts, terminology and systems to underpin the international chemical measurement system. References are given to a number of papers covering specific parts of the programme.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Springer
    Accreditation and quality assurance 4 (1999), S. 360-365 
    ISSN: 1432-0517
    Keywords: Key words Reference materials ; Accreditation ; Quality systems
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract  The use of reference materials is the most pragmatic means by which the analyst can achieve comparability of data. Reference material producers therefore need to have adequate quality systems in place for ensuring the reliability of their materials. In order to provide guidance to both producers and assessors, ISO Guide 34 has recently been produced detailing the quality system requirements for the production of reference materials. CITAC, REMCO and ILAC are now collaborating in the revision of this guide to produce a free-standing document detailing the general requirements for the competence of reference material producers. This paper discusses some of the more important issues described in these documents. The possible formation of an international register containing details of a reference material producer's quality system status is also discussed.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 595 (1990), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK; Malden , USA : Blackwell Science Inc
    Restoration ecology 12 (2004), S. 0 
    ISSN: 1526-100X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Induced mycorrhization of sweet birch (Betula lenta L.) by Pisolithus tinctorius (Pers.) Coker & Couch, as influenced by substrate fertility, was evaluated for its effects on seedling growth and physiology. Following a brief period in seed flats, seedlings were transplanted to mine spoil where they resided for 30 months, and three nutrition regimes were imposed throughout the study by application of differing nutrient solution concentrations. High fertility suppressed mycorrhizal formation by P. tinctorius but promoted that of other mycobionts. Pisolithus mycorrhization induced substantial aboveground and belowground growth as indicated by dimensions and mass for the former and mass and length for the latter but favoring root over shoot growth overall. Furthermore, these mycorrhizae were frequently able to compensate for the growth stimulation of higher nutrient additions. Measurements of xylem pressure potential and soil water potential indicated that water uptake was enhanced by P. tinctorius during simulated drought episodes of two durations and in subsequent recovery periods. Inoculated seedlings had higher foliar concentrations of critical nutrients, especially N, and lower concentrations of potentially phytotoxic metallic elements, particularly Mn, than uninoculated seedlings, although the latter response was absent in high fertility. Spoil analyses clearly revealed the influence of the nutrition regimes but also the effects of seedling uptake on substrate chemistry, and reinforced the findings of the foliar analysis concerning suppression of metal uptake by P. tinctorius. Collectively, these results suggest that P. tinctorius can provide sweet birch an array of physiological benefits that will permit this tree species to flourish on harsh substrates such as surface mine spoils without heavy application of chemical fertilizers.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Grass and forage science 14 (1959), S. 0 
    ISSN: 1365-2494
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: An experiment conducted in south-west Scotland during 1956 and 1957 to investigate an outdoor method of rearing calves on pasture, with and without supplementary food, is described.Twenty-four Ayrshire bull calves were put on pasture at 2 weeks of age and received an average of 37 gallons of whole milk up to the time they were weaned at 8 weeks old. Twelve of the calves received no supplementary feeding, but the other twelve each ate 257 lb. of a meal containing oats, linseed cake, flaked maize and fish meal from their 3rd to their 20th week.The calves were moved around a series of plots (0.4 acre) which yielded an average of 1400 lb. of dry matter per acre at each grazing. The mean crude protein of the herbage dry matter was 17.4% in 1956 and 14.1% in 1957.The mean daily liveweight-gains of the calves from birth to 20 weeks of age were 1.05 lb. for the unsupplemented calves and 1.14 lb. for the supplemented ones—a non-significant difference, as was also the difference between the mean increases in belly-girth measurements of the two groups.Parasitic infestation of the two groups was extremely low and 83% of all faeces samples examined contained no worm eggs.The latest-born calves made the poorest liveweight gains.The outdoor rearing of calves is discussed.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Boston, MA, USA : Blackwell Science Inc
    Restoration ecology 10 (2002), S. 0 
    ISSN: 1526-100X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Controlled-release fertilization with two formulations, Forestcote 22-4-6 + Minors and Gromax 21-6-2 + Minors, and dolomitic lime were evaluated for their capacity to facilitate establishment and enhance nutrition of bareroot Jeffrey pine (Pinus jeffreyi Grev. & Balf.) on an acidic Sierra Nevada surface mine. All amendments were applied at outplanting to the backfill of augered planting holes, with a low rate of 8 g and a high rate of 16 g per seedling for the two fertilizer formulations, whereas a single rate of 30 g was used for lime. Liming induced excessive seedling mortality throughout the study, whereas both fertilizer formulations also reduced survival but only as an interactive effect with the lime amendment. Growth stimulation by the fertilizer applications was readily apparent after three growing seasons, with the response to the high rate surpassing that to the low rate and the response to the Forestcote formulation exceeding that to Gromax. Conversely, the lime amendment depressed seedling growth, and it is likely that a propensity to exacerbate the stress imposed by dry growing season soils through interference with water uptake accounts for the overall poor performance of the seedlings that received this amendment. Improved N and P nutrition, with the former likely the most critical, was largely responsible for the growth stimulation resulting from fertilization. However, this treatment also suppressed the absorption of certain micronutrients as well as that of Al, and the amelioration of potential phytotoxicities may have also contributed to the favorable performance of fertilized seedlings. Further evidence for this conclusion was supplied by base cation/metallic element molar ratios involving Al and Mn, which were frequently increased by fertilization. In contrast, the influence of the lime amendment on seedling nutrition was marginal, with positive responses too infrequent to improve seedling performance.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Boston, MA, USA : Blackwell Science Inc
    Restoration ecology 11 (2003), S. 0 
    ISSN: 1526-100X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract A comparison of a composted organic amendment, a controlled-release fertilizer, and induced mycorrhizal inoculation as affecting the establishment and nutrition of bareroot Jeffrey pine (Pinus jeffreyi Grev. & Balf.) was conducted on a Sierra Nevada surface mine. The soil amendments were applied at outplanting to the backfill of augered planting holes, with a low rate of 8 g and a high rate of 16 g per seedling for the fertilizer, Gromax 21-6-2 + Minors, whereas a single rate of 2.0 L was used for organic matter. Colonization by Pisolithus tinctorius (Pers.) Coker & Couch was induced by coating the root systems with basidiospores suspended in a gel carrier. The organic amendment especially, but also mycorrhizal inoculation, caused substantial seedling mortality, whereas survival was unaffected by controlled-release fertilization. Gromax applied at the high rate produced a 74% increase in shoot volume after three growing seasons, whereas the organic amendment reduced volume by 28%. Growth was unaffected by mycorrhizal treatment. The growth response to the 16-g Gromax application probably reflected enhanced N, P, and K nutrition and decreased concentrations of potentially toxic metallic elements, including Mn and Al among others, as revealed through foliar analysis. Because they were accompanied by growth reduction, nutritional responses to the organic amendment, which involved both macronutrients and trace elements, were of little consequence. Impaired water relations may account for the poor response to this amendment. Likewise, nutritional responses to mycorrhizal inoculation produced no discernible benefit in terms of seedling performance. An inoculation procedure that failed to induce substantially greater P. tinctorius colonization in inoculated than uninoculated seedlings, and that may have also impaired water relations, likely explains this result. Overall, these findings indicate that further research is needed before either the organic amendment or the mycorrhizal inoculation procedure used here can be used in forest restoration efforts on dry sites.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 88 (1981), S. 0 
    ISSN: 1471-0528
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Fifteen women with normal menstrual cycles, dated by accepted criteria, had salivary progesterone concentrations during' the luteal phase of the cycle which were significantly higher than those in the follicular phase. Progesterone concentrations in matched samples of plasma and saliva showed excellent correlation in both normal and infertile women. Salivary progesterone profiles derived from daily sampling of 20 infertile patients not only allowed accurate assessment of ovarian dysfunction but also indicated more effectively than conventional techniques the change in hormonal status following ovulation induction therapy with clomi-phene citrate or bromocriptine.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 458 (1985), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of pineal research 3 (1986), S. 0 
    ISSN: 1600-079X
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: The purpose of this study was to examine the temporal effects of norepinephrine (NE) stimulation on pineal serotonin (5HT) in vitro. Rat pineal glands were individually incubated in nutrient media for 6 h. After a 2-h preincubation, the glands were exposed to tryptophan (TRYP) or TRYP + norepinephrine (10−4 M each) for 4 additional h. Media and pineals were then analyzed for 5HT and 5HIAA content. Initial exposure to TRYP increased 5HT levels in the media. Norepinephrine increased media 5HT concentrations further and also caused 5HIAA levels to rise significantly. These findings suggest that 5HT secretion and/or oxidation is an early response to stimulation of the pineal gland by NE. Following prolonged NE exposure, media 5HT declined to control values while 5HIAA remained high. Similarly, intrapineal levels of 5HT fell after prolonged stimulation with NE. Thus, pineal responses to initial and continued stimulation with NE are differentiable as early and late effects upon 5HT. Early effects may include secretion and/or oxidation of 5HT followed later by utilization of 5HT in N-acetylation pathways such as that leading to melatonin synthesis. The finding that 5HT is secreted in response to NE suggests that the indoleamine may be a hormone of the pineal gland. Based upon its known influence on physiologic rhythms, daily secretion of 5HT from the pineal may be an important part of the gland's time-keeping function.
    Type of Medium: Electronic Resource
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