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61.
Martin Funk 《Geometriae Dedicata》1988,28(1):53-75
A projective confined configuration with axis and centre will be introduced in terms of a non-degenerate octagon
satisfying some hypotheses on the position of its diagonal points (i.e. intersections of edges having distance 8 in the flag graph (
)) and its first minor diagonal lines (i.e. diagonal lines joining vertices of distance 6 in (
)). That confined configuration gives rise to a certain configurational condition whose affine specialization (i.e. the axis coincides with the line at infinity) is equivalent to the affine Pappos condition, whereas its little specialization (i.e. the centre lies on the axis) turns out to be equivalent to the little Desargues condition. In Pappian projective planes can be completed to a configuration of type (124, 163). 相似文献
62.
Rational Design of [13C,D14]Tert‐butylbenzene as a Scaffold Structure for Designing Long‐lived Hyperpolarized 13C Probes
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Yuki Imakura Dr. Hiroshi Nonaka Dr. Yoichi Takakusagi Prof. Dr. Kazuhiro Ichikawa Nesmine R. Maptue Dr. Alexander M. Funk Prof. Dr. Chalermchai Khemtong Prof. Dr. Shinsuke Sando 《化学:亚洲杂志》2018,13(3):280-283
Dynamic nuclear polarization (DNP) is a technique to polarize the nuclear spin population. As a result of the hyperpolarization, the NMR sensitivity of the nuclei in molecules can be dramatically enhanced. Recent application of the hyperpolarization technique has led to advances in biochemical and molecular studies. A major problem is the short lifetime of the polarized nuclear spin state. Generally, in solution, the polarized nuclear spin state decays to a thermal spin equilibrium, resulting in loss of the enhanced NMR signal. This decay is correlated directly with the spin‐lattice relaxation time T1. Here we report [13C,D14]tert‐butylbenzene as a new scaffold structure for designing hyperpolarized 13C probes. Thanks to the minimized spin‐lattice relaxation (T1) pathways, its water‐soluble derivative showed a remarkably long 13C T1 value and long retention of the hyperpolarized spin state. 相似文献
63.
The MELANIE project: from a biopsy to automatic protein map interpretation by computer. 总被引:3,自引:0,他引:3
R D Appel D F Hochstrasser M Funk J R Vargas C Pellegrini A F Muller J R Scherrer 《Electrophoresis》1991,12(10):722-735
The goals of the MELANIE project are to determine if disease-associated patterns can be detected in high resolution two-dimensional polyacrylamide gel electrophoresis (HR 2D-PAGE) images and if a diagnosis can be established automatically by computer. The ELSIE/MELANIE system is a set of computer programs which automatically detect, quantify, and compare protein spots shown on HR 2D-PAGE images. Classification programs help the physician to find disease-associated patterns from a given set of two-dimensional gel electrophoresis images and to form diagnostic rules. Prototype expert systems that use these rules to establish a diagnosis from new HR 2D-PAGE images have been developed. They successfully diagnosed cirrhosis of the liver and were able to distinguish a variety of cancer types from biopsies known to be cancerous. 相似文献
64.
Cytokine production after helium-neon laser irradiation in cultures of human peripheral blood mononuclear cells. 总被引:5,自引:0,他引:5
J O Funk A Kruse H Kirchner 《Journal of photochemistry and photobiology. B, Biology》1992,16(3-4):347-355
The effects of laser light on the immune system have not been extensively characterized. Low-power laser sources, such as the helium-neon (He-Ne) laser with a wavelength of 632.8 nm, have been found to produce photobiological effects with evidence of interference with immunological functions. We have investigated the effects of He-Ne laser irradiation on Ficoll-Hypaque-isolated human peripheral blood mononuclear cells (PBMC). Cultured cells were irradiated for various times at two selected intensities and then stimulated with different mitogens. The rate of incorporation of 3H-thymidine into the DNA of stimulated cells decreased with increasing energy density. The levels of interleukin-1 alpha (IL-1 alpha), interleukin-2 (IL-2), tumour necrosis factor-alpha (TNF-alpha) and interferon-gamma (IFN-gamma) in supernatants of the cultures were determined (irradiated either before or after stimulation). When stimulating cells after irradiation, significantly increased levels of all cytokines were detected after 30 min of irradiation (18.9 J cm-2), whereas after 60 min of irradiation (37.8 J cm-2) cytokine levels were found to be significantly decreased. 相似文献
65.
W. Funk 《Fresenius' Journal of Analytical Chemistry》1906,45(3-4):181-196
Zusammenfassung Zuerst sei nochmals auf die ebenso einfache als mühelose Art der Vorbereitung der betreffenden Ferrilösung für die Fällung des basischen Eisenazetates hingewiesen, nämlich durch Eindampfen der salzsauren Flüssigkeit auf dem Wasserbade und Wiederaufnehmen mit Wasser, wodurch stets eine gleichmäfsig schwach saure Lösung erhalten wird, im Gegensatz zu den sonst meist üblichen Neutralisationsverfahren.Die Azetatmethode liefert bei einmaliger Ausführung sowohl für die Trennung des Eisens von Mangan als auch von Nickel, Kobalt und Zink richtige Werte, wobei man jedoch die Verhältnisse von der Fällung mit Ammoniumazetat nur mutatis mutandis auf die mit Natriumazetat übertragen darf. Bei der im Allgemeinen wohl häufigeren Anwendung des letzteren Salzes ist die Arbeitsweise am einfachsten folgende: Die Metallchloridlösung wird, unter Zusatz von etwa 0,35g Kaliumchlorid auf 0,1g Eisen, in einer geräumigen Schale auf dem Wasserbade eingedampft, darauf der Rückstand oberflächlich zerrieben, noch einige Minuten erhitzt und dann in 10–20cc Wasser gelöst. Man braucht mit dem Verjagen der freien Säure nicht übermäfsig behutsam zu verfahren; es soll sogar eine geringe Menge zurückbleiben, zur Bildung freier Essigsäure, wofür man dann letztere als solche nicht zusetzt. Hierauf gibt man zur konzentrierten Ferrilösung die anderthalbfache bis doppelte Menge des theoretisch erforderlichen Natriumazetates zu. Letzteres hatte man in Wasser gelöst und die Lösung, wenn nötig, schwach mit Essigsäure angesäuert. Nun verdünnt man, bei 0,2g Eisen auf 400–500cc, erhitzt unter Umrühren allmählich auf 60–70°, bei welcher Temperatur sich der Niederschlag abscheidet, lässt absitzen, dekantiert, bringt den Niederschlag auf's Filter und wäscht mit heissem Wasser aus.Aus dem chem. Labor. d. kgl. Bergakademie Freiberg Sa. 相似文献
66.
Substituted 2-aryl-propionaldehydes tautomerize in dimethyl sulfoxide to the corresponding enoles. The ratio of the tautomers can be described by Hammett σ-values, as in the case of imin-enamine-tautomeric 2-aryl-propionaldehyde methylimines. This is the first example of a linear free energy relationship between the two forms of tautomerism. 相似文献
67.
Funk S. B. Crawford D. L. Crawford R. L. Mead G. Davis-Hoover W. 《Applied biochemistry and biotechnology》1995,51(1):625-633
Applied Biochemistry and Biotechnology - An anaerobic bioremediation process for the degradation of nitroaromatic compounds in soil was demonstrated. Thisex situ process was demonstrated full-scale... 相似文献
68.
69.
A concise diastereoselective total synthesis of (-)-nakadomarin A has been completed in 21 steps from D-pyroglutamic acid. Key steps include an enecarbamate Michael addition/furan-N-acyliminium ion cascade cyclization to provide the tetracyclic core and ring-closing alkyne and alkene metatheses to construct the fifteen- and eight-membered azacycles, respectively. 相似文献
70.
[reaction: see text] The rapid construction of the tetracyclic core ring system of nakadomarin A via a tandem enecarbamate Michael addition/N-acyliminium ion cyclization is described. 相似文献