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  • 1
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 66 (1995), S. 2021-2029 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Optical elements need to be developed at least at the same pace as synchrotron radiation sources of the third generation. We are concerned here with the interrelationship between improved optical instruments and scientific progress. This relationship becomes especially clear in the development of new monochromators with higher resolution and large throughput. The availability of better mirrors and gratings is most important in this respect. Another field is microscopy. We shall be concerned here mainly with scanning microscopy in which the radiation is imaged with mirrors onto a small spot on the sample. The respective imaging with zone plates is the topic of another paper. A spot size of 0.1 μm and better is theoretically feasible with mirrors but it depends on much progress in the manufacturing of aspherical mirrors of high accuracy. We demonstrate mainly from our own results with a spot in the 1 μm range that it is worthwhile to make this effort. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 66 (1995), S. 3513-3519 
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: The first attempt to combine luminescence spectroscopy with scanning soft x-ray microscopy has been realized in our experiment. A new imaging luminescence spectrometer with a Schwarzschild objective was designed and built with a spectral resolution of 1.3 nm in the energy range of 1.6–6.5 eV for this purpose. Some luminescent ceramics have been investigated by using this spectrometer. A high contrast in luminescence micrographs is achieved due to the confocal arrangement of the Schwarzschild system and the microscope. The spectral and microstructural properties of these ceramics could be determined by means of luminescence microspectroscopy and spectromicroscopy. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Copenhagen : Blackwell Publishing Ltd
    Allergy 54 (1999), S. 0 
    ISSN: 1398-9995
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Background: Breast milk is thought to contain its own complex immune system. Whether or not this is altered in allergic individuals is not yet known. Methods: By ELISA techniques, inflammatory markers (MIP-1α, sICAM-1) and TH1 (interferon-gamma [IFN-γ]), as well as TH2 cytokines (interleukin [IL]-4, IL-10), were investigated in serum and milk samples from nonallergic (n=23) lactating women and those with respiratory allergies (n=19) during the first week postpartum. Results: IFN-γ was not detected in either serum or milk. IL-10 was more often found to be above the detection limit in both milk and serum samples from allergic mothers. IL-4 was detected in almost all serum samples with a wide variation. In milk, IL-4 was found in about 20% of the samples. MIP-1α was not detected in the serum but was detected in the milk of 23% of the nonatopic and 53% of the allergic mothers. Soluble ICAM-1 was present in all samples. Surprisingly, serum levels of sICAM-1 in allergic mothers (271±97 ng/ml) were significantly lower (P〈0.001) than in nonatopic subjects (375±86 ng/ml). Concentrations of sICAM-1 in milk were similar in both groups. Conclusions: The concentrations of proinflammatory markers and cytokines in breast milk did not differ significantly between allergic and nonatopic mothers. In some individuals, high levels of MIP-1α, IL-10, and sICAM-1 could be found. However, the significance of these components for the breast-fed infant is still unclear.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1436-6215
    Keywords: Kraftsportler ; hohe Proteinzufuhr ; renale Nettosäureausscheidung ; Urin pH ; Ammoniumausscheidung ; Ammoniumproduktion ; renale Säureausscheidungskapazität ; Sulfat ; Bodybuilder ; high protein diet ; renal net acid excretion ; urine-pH ; ammonium excretion ; ammonia production ; sulfate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary Bodybuilders often prefer a high protein diet to achieve maximum skeletal muscle hypertrophy. In this study the effect of a high protein diet on renal acid load and renal handling of proton excretion was studied comparing dietary intake and urinary ionograms in 37 male bodybuilders and 20 young male adults. Energy intake (+7 %), protein intake (128 vs 88 g/d/1.73 m2), and renal net acid excretion (95 vs 64 mmol/d/1.73 m2) were higher in the bodybuilders than in the controls, however, urine-pH was only slightly lower (5.83 vs 6.12). In the bodybuilders renal ammonium excretion was higher at any given value of urine pH than in the controls. In a regression analysis protein intake proved to be an independent factor modulating the ratio between urine-pH and renal ammonium excretion. The concomitant increase of renal net acid excretion and maximum renal acid excretion capacity in periods of high protein intake appears to be a highly effective response of the kidney to a specific food intake leaving a large renal surplus capacity for an additional renal acid load.
    Notes: Zusammenfassung Kraftsportler ernähren sich zur Förderung des Muskelwachstums häufig proteinreich. In dieser Studie wurde die Wirkung einer hohen Proteinzufuhr auf die renale Säurelast und die renale Säureausscheidungskapazität anhand des Vergleichs der Daten der Nährstoffzufuhr und der Harnionogramme von 37 Kraftsportlern mit hoher Proteinzufuhr und 20 jungen Erwachsenen mit normaler Proteinzufuhr (Vergleichsgruppe) untersucht. Die Kraftsportler zeigten eine höhere Energie-(+7 %) und Proteinzufuhr (128 vs 88 g/d/1.73 m2) und eine höhere renale Nettosäureausscheidung (95 vs 64 mmol/d/1.73 m2) als die Vergleichsgruppe. Die Differenz der Urin pH-Werte der beiden Gruppen war allerdings erstaunlich gering (5.83 vs 6.12). Bei den Kraftsportlern war die renale Ammoniumausscheidung bei allen Urin pH-Werten deutlich höher als bei der Vergleichsgruppe. Eine Regressions-analyse ergab, daß die Proteinzufuhr das Verhältnis von Urin pH und renaler Ammoniumausscheidung eigenständig zu beeinflussen vermag. Eine vermehrte Proteinzufuhr führt zu einer erhöhten renalen Säurelast und Nettosäureausscheidung. Die gleichzeitig auftretende Steigerung der renalen Säureausscheidungskapazität infolge einer erhöhten Ammoniumproduktion stellt einen sinnvollen Anpassungsmechanismus des Körpers an diese besondere Form der Ernährung dar, der dem Körper eine ausreichende funktionelle Reservekapazität für weitere den Säure-Basen-Haushalt belastende pathophysiologische Ereignisse erhält.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Experimental astronomy 9 (1999), S. 17-38 
    ISSN: 1572-9508
    Keywords: Radio Astronomy ; Array Systems ; Acousto-Optical Spectrometer ; Back-ends ; Radiometers ; Heterodyne Instrumentation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract In this paper an array acousto-optical spectrometer (AOS) with four 1 GHz bands and a frequency channel spacing of 1 MHz is presented. A discussion about the requirements which have to be fulfilled by the presented instrument for applications in radio astronomy is given as well as e detailed description of the optical design. Remarkable test results have been achieved such as an Allan-Variance minimum time of about 1000 s, identical noise performance, and identical frequency calibration of all bands. The reproducibility of measurements has been demonstrated by tests with CH3CN, using an absorption cell. The question of the maximum number of bands per array AOS is discussed. Although it may seem promising to increase the number of bands per optical unit to e.g. eight or more instead of four, a strong limitation has been found due to the increasing r.f. power level on the Bragg cell which affects the baselines of the spectra.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    European journal of clinical microbiology & infectious diseases 18 (1999), S. 467-472 
    ISSN: 1435-4373
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  To study the epidemiology of hantavirus infections in Austria, 1215 humans and 596 rodents of different species were tested for the presence of antibodies against Puumala and Hantaan virus. Direct virus identification by polymerase chain reaction in lung tissue of serologically positive rodents was performed to verify antibody results and to determine the genetic identity of viral RNA by phylogenetic analysis of a part of the hantavirus M segment. For 32 of the 37 cases of nephropathia epidemica diagnosed in Austria, the location where transmission took place could be traced to specific areas in the Austrian federal states of Carinthia and Styria. The overall seroprevalence in humans was 1.2% and ranged from 0.02% in Villach, Carinthia, to 0.8% in Korneuburg, Lower Austria, and 1.8% in Wolfsberg, Carinthia. Virus RNA could be amplified from three Clethrionomys glareolus voles collected in Klippitztörl, Carinthia, and from one collected in Ernstbrunn, Lower Austria. The sequences were all identified as Puumala virus by phylogenetic analysis and were found to be most closely related to the western European Puumala viruses from Germany and France. No evidence of the existence of Hantaan-like infections and viruses in Austria was found.
    Type of Medium: Electronic Resource
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  • 7
    ISSN: 1432-8798
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary A set of ten monoconal antibodies (mabs) specific for the tick-borne encephalitis (TBE) virus envelope protein E were prepared and characterized with respect to their functional activities, the location of their binding sites on protein E and the involvement of their epitopes in acid pH-induced conformational changes and interactions with the precursor to the membrane protein (prM) in immature virions. The majority of these mabs mapped to the previously defined antigenic domain A. All of the mabs recognize parts of the E protein which undergo low pH-induced structural rearrangements believed to be necessary for the fusion activity of the virus, and six of the mabs define epitopes which are affected by the prM-E interaction in immature virions. They are therefore of potential value as specific reagents for studying the structure and function of protein E, as well as the function of the prM-E association. Five of the mabs exhibited neutralizing activity, and can therefore be used for the selection of escape mutants.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 1617-4623
    Keywords: Key wordsAgrobacterium tumefaciens ; Chitinase ; Gene silencing ; Nicotiana sylvestris ; Ti plasmid
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Agroinfiltration – the infiltration of Agrobacterium tumefaciens into intact plant leaves – provides a rapid and simple way of screening large numbers of transgene constructs for silencing in response to a resident transgene. Transgenic Nicotiana sylvestris plants homozygous for the tobacco class I chitinase A gene CHN48 under the control of the cauliflower mosaic virus 35S RNA promoter (P35S) show a high incidence of postranscriptional gene silencing. We forced suspensions of A. tumefaciens, carrying P35S-CHN48 in a binary Ti-plasmid vector, into wild-type and transgenic N. sylvestris leaves with a blunt-tipped plastic syringe. The infiltrated CHN48 transgene was expressed in leaves transformed with the vector alone, but not in CHN48-transformed leaves showing the silent phenotype. In contrast, expression of a chimeric P35S-E. coliβ-glucuronidase gene (uidA) infiltrated into leaves was not affected by the presence of the CHN48 transgene stably integrated in the host genome. These results show that extra copies of CHN48 are silenced by resident, silent copies of the same gene and confirm that CHN48 silencing is not the result of promoter interactions. The results also suggest that silencing of the additional CHN48 copies does not require their integration into chromosomes.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Fresenius' Zeitschrift für analytische Chemie 353 (1995), S. 494-498 
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The availability of synchrotron radiation from undulators is the basis of a new probe of tunable X-rays. The realization of such a probe requires to produce a demagnified image of the monochromatized radiation from the source on the sample. For this purpose Fresnel zone plates, multilayer covered mirrors, and mirrors at grazing incidence are available. The probe sizes presently are between 30 nm and 1 μm. In the scanning microscope at HASYLAB/DESY in Hamburg a grazing incidence ellipsoid mirror is used to focus radiation in the energy range 15 eV to 1200 eV to a spot of 1 μm. In the VUV-region below 30 eV a normal incidence Schwarzschild objective allows a spatial resolution of 100 nm. The signals which are available for microscopy and microspectroscopy are transmission, photoelectrons, luminescence in the visible, UV and soft X-ray regions, scattered light and desorbed ions. Spectrometers for photoelectrons and visible/UV-luminescence are installed for secondary spectroscopy. Several of the signals are not only element specific but also specific to the chemical environment and binding character. Most of the techniques are very surface sensitive. Different projects are reviewed while we concentrated mainly on examples from our own station.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    European journal of nutrition 35 (1996), S. 22-31 
    ISSN: 1436-6215
    Keywords: Oligosaccharide ; Frauenmilch ; Kuhmilch ; Säuglingsformulae ; Lactose-derived oligosaccharides ; human milk ; bovine milk ; infant formula
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Description / Table of Contents: Summary About a century ago, pediatricians observed that in feces of breast-fed infants, compared to those of bottle-fed infants,Bifidobacterium bifidum was the predominant microorganism. It was shown thereafter that aminosugarcontaining oligosaccharides are growth factors for a specific strain of Bifidobacterium. Meanwhile, more than 130 lactose-derived oligosaccharides have been identified in human milk. Some of these oligosaccharides like Lacto-N-Tetraose and Lacto-N-Fucopentaose I and II do not occur in minute amounts but in concentrations up to 1–2 g/L. As the total amount of complex oligosaccharides is between 3–6 g/L those components have to be considered as major human milk constituents. There is striking evidence that human milk oligosaccharides are potent inhibitors of bacterial adhesion to epithelial surfaces, an initial stage of infective processes. Therefore, these oligosaccharides are considered to be soluble receptor analogues of epithelial cell surfaces participating in the non-immunological defense system of human milk-fed infants.
    Notes: Zusammenfassung Um die Jahrhundertwende beobachtete man, daß bei gestillten Kindern die Keimbesiedlung des Darmtraktes vorwiegend aus Bifidusbakterien besteht. Bei sog. Flaschenkindern dagegen fand man eine wesentlich ungünstigere Zusammensetzung der Darmflora mit vorwiegend pathogenen Keimen. Mitte der 50er Jahren wurde nachgewiesen, daß dieses Wachstum auf Oligosaccharide in Frauenmilch, die Aminozucker enthalten, zurückzuführen ist. Mittlerweile sind mehr als 130 Oligosaccharide in Frauenmilch charakterisiert worden, die teilweise fucosyliert und/oder sialyliert sind. Die Konzentrationen einzelner Komponenten wie der Lacto-N-Tetraose und der beiden Lacto-N-Fucopentaosen I und II schwanken zwischen 0,5 und 2 g/L. Da der Gesamtgehalt zwischen 3–6 g/L liegt, muß man sie zu den Hauptmilchinhaltsstoffen zählen. Unterschiede sowohl im Gehalt als auch im Muster zwischen Milch von Frauen mit Früh- und solchen mit Reifgeburten wurden bisher nicht festgestellt. Es gibt immer mehr Hinweise darauf, daß Oligosaccharide in Frauenmilch potentielle Inhibitoren der Anhaftung von Bakterien und Viren an Epithelzellen sind, wodurch der erste Schritt eines Infektionsvorgangs beeinflußt werden könnte. Daher werden solche Oligosaccharide als lösliche Rezeptoranaloga zu Kohlenhydratstrukturen auf Epithelzellen angesehen, die möglicherweise zu einer besseren Infektabwehr von Neugeborenen führen, die mit Frauenmilch ernährt werden.
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