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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 104 (1996), S. 942-949 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We investigated dimethyl-s-tetrazine (-h6 and -d6) in a n-heptane (-h16 and -d16) lattice with hole burning techniques. Stark experiments definitely show that the two methyl groups in dimethyl-s-tetrazine (DMST) are inequivalent. Hence, the respective rotational tunneling dynamics can be different. This is clearly seen in the behavior of DMST-d6 in both lattices n-heptane-h16 and -d16: Hole burning produces three pairs of sideholes symmetrically shifted from the laser frequency. The tunneling dynamics of the central hole as well as of the sideholes is governed by two relaxation times which differ by about one order of magnitude. Due to the narrow temperature range accessible, an unambiguous assignment of the microscopic tunneling relaxation process is not possible. On the other hand, DMST-h6 relaxes via a Raman process above 3 K and via a direct process below. In the Raman-active regime the tunneling rates for both host lattices fall on top of each other in agreement with theory. There are, however, features in the tunneling dynamics which are not yet understood. For instance, in the temperature regime where the direct process prevails, host deuteration speeds up the tunneling relaxation by an order of magnitude. In addition, the sidehole pattern of DMST-h6 is quite different from DMST-d6: Only one pair is observed. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 105 (1996), S. 9762-9770 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Rotational tunneling of monodeuterated methyl groups of dimethyl-s-tetrazine guest molecules in n-octane and tetramethylbenzene crystalline matrices is characterized by optical spectroscopy including hole burning methods. An analysis of the level structure shows that the asymmetric substitution leads to a partial localization of one of the methyl groups in n-octane, while in the tetramethylbenzene host both groups are equivalent and are strongly localized. The relaxation, by incoherent tunneling, between different orientations proceeds on a time scale of 〉107 s−1 in n-octane at temperatures below 2 K. The coupling of the orientation of the methyl group with the environment is estimated from information on inhomogeneous broadening attributed to random strain fields in the crystal. The strength of this coupling is related to the observed relaxation behavior. The origin of the asymmetry of the rotational potential is discussed in terms of static and dynamic contributions which are due to changes of bond length upon isotopic substitution and the dependence of vibrational frequencies on orientation. © 1996 American Institute of Physics.
    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 105 (1996), S. 1798-1806 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We performed two different types of spectral diffusion experiments on persistent spectral holes. In all cases, we measured the holewidth as a function of time. The two experiments differed in their initial conditions: In the type 1 experiment (the "aging experiment''), the sample was cooled from room temperature to the final temperatures which were 100 and 800 mK, respectively. Holes were burnt at various time intervals after the final temperature was reached. In the type 2 experiment (the "cycling experiment''), the sample was allowed to relax for a period of about 10 days. Then, a hole was burnt and subjected to a temperature cycle. In all cases, the time dependence of the holewidths was strongly nonlogarithmic. The temperature cycled hole showed a narrowing regime which prevailed for the whole observation period of roughly one week. We will show that the deviation from the logarithmic time dependences is a nonequilibrium phenomenon. All features observed could be modelled within the standard tunneling model. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-0584
    Keywords: Key words Bisphosphonate ; Multiple myeloma ; Pulmonary calcification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  A-52-year-old patient presented with a 2-year history of multiple myeloma, recurrent episodes of hypercalcemia, and extensive bone involvement. She developed pulmonary infiltrates, initially misdiagnosed as interstitial pneumonia. High-resolution computed tomography and bone scintiscanning indicated pulmonary calcification, which was confirmed by a transbronchial biopsy. Cytostatic treatment of multiple myeloma in combination with repetitive i.v. administration of bisphosphonates over a period of 6 months led to a significant improvement of clinical symptoms. Regression of pulmonary infiltrates was demonstrated by chest radiograph and computed tomography. There are only a few reports on pulmonary calcification in patients with multiple myeloma; the condition was associated mostly with progressive disease, kidney failure, adult respiratory distress syndrome and bad prognosis. In our patient isolated calcification of the lungs without involvement of other organ systems was successfully treated. These findings suggest that interstitial pulmonary calcinosis in multiple myeloma can be reversed by normalization of serum calcium levels using bisphosphonates combined with cytostatic treatment.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1434-601X
    Keywords: 13.60.Le
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The reactione+p →〉 e+π ++n at c.m. energyW=1125MeV and momentum transfer Q2=0.117GeV2/c2 has been measured. The transverse and longitudinal structure functions have been separated by varying the polarization of the virtual photon (Rosenbluth plot) with a 3 to 4% error. In addition the longitudinal-transverse interference term has been determined measuring the right-left asymmetry with an accuracy of 3%. The experimental data are compared to model calculations, and the sensitivity of the results to the axial and pion formfactors is discussed.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1573-5060
    Keywords: common wheat ; Triticum aestivum ; powdery mildew ; resistance gene ; monosomic analysis ; gene location
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary Common wheat cultivar Virest possesses mildew resistance which is different from resistances expressed by currently documented mildew resistance genes, detected by response to eleven differential wheat powdery mildew isolates. F2 populations from hybrids of the 21 ‘Chinese Spring’ monosomic lines with ‘Virest’ revealed one major dominant gene, located on wheat chromosome 1D. The new gene is designated Pm22. Italian cultivars Elia, Est Mottin, Ovest and Tudest also showed the disease response pattern corresponding to ‘Virest’.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Biotechnology techniques 10 (1996), S. 991-996 
    ISSN: 1573-6784
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Notes: Summary During the study of mevinolin biosynthesis by Aspergillus terreus ATCC 20542, 10 different medium components were selected for medium optimization. A new optimization method based on genetic algorithms and inductive learning was used for experimental design. For better efficiency the method was supported by a model, constructed with machine learning method, to predict the productivity. In four generations of fermentation experiments the productivity increased nearly three times.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Genetic resources and crop evolution 43 (1996), S. 91-96 
    ISSN: 1573-5109
    Keywords: Secale vavilovii ; weedy rye ; translocations ; isozymes ; cluster analysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Notes: Summary The accurate identification and classification of wild species enhance the utilization of potential plant genetic resources. The wild rye species Secale vavilovii Grossh. may serve to broaden the genetic variation in cultivated rye, S. cereale. The combined analyses of cytological, isozymic and other genetic characteristics in the present study revealed that of the fourteen rye accessions designated as S. vavilovii, only three accessions were correctly classified. Thus it is essential to increase multidisciplinary, international research and collaboration to aid in the classification and utilization of the yet untapped plant germplasm.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Langenbeck's archives of surgery 381 (1996), S. 333-336 
    ISSN: 1435-2451
    Keywords: Notfalleingriffe in der Darmchirurgie ; Anastomosenstoma
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Zusammenfassung In der Notfallchirurgie erscheint eine primäre Darmanastomose oft als risikoreich. Diskontinuitätsresektionen haben den Nachteil einer 2. Laparotomie zur Wiederherstellung der Kontinuität. Wenn eine ausreichende Mobilisation der betroffenen Darmabschnitte möglich ist, bevorzugen wir die Anlage eines Anastomosenstomas. Nach Resektion des erkrankten Darmabschnitts werden die zu- und abführende Schlinge gemeinsam durch eine Bauchdeckentrepanation vor die Bauchdecke gelagert und die Hinterwände der Schlingen anastomosiert. Die vordere Darmwand bleibt unverschlossen und wird in mukokutaner Technik als Stoma eingenäht. Bisher haben wir diese Methode bei 91 Patienten angewandt, 73mal handelte es sich um Notfalleingriffe. Kein Patient starb an Komplikationen, die methodenbedingt waren, 21mal führte allerdings die Grunderkrankung zum Tod des Patienten. Die Darmkontinuität konnte in 78 Fällen wiederhergestellt werden. Das Anstomosenstoma schützt die Rückwand vor erhöhtem Druck und erlaubt die tägliche Kontrolle der Anastomose. Bei extraperitonealer Rückverlagerung des Stomas entfällt die erneute Laparotomie zur Kontinuitätswiederherstellung. Die Anlage des A nastomosenstomas ist in den meisten Dünn- und Dickdarmabschnitten möglich.
    Notes: Abstract In emergency surgery of the bowel a primary anastomosis may be risky. Discontinuing colostomies have the disadvantage that a secondary laparotomy is necessary to restore continuity. If sufficient bowel loop mobilization is possible, we prefer to perform an anastomotic stoma. After resection of the diseased bowel segment, we bring the proximal and distal loop together and proceed to the anastomosis of the posterior wall. The anterior wall of the anastomosis remains open and is then fixed to the abdominal wall as a stoma. So far, we have used this method in 91 patients. In 73 cases this technique was performed during emergency operations. No patient died as a result of complications of the method; 21 patients, however, died as a consequence of their primary disease. Bowel continuity could be restored in 78 cases. The anastomotic stoma protects the posterior wall from elevated pressure and allows daily control of the anastomosis. In the case of extraperitoneal closure, a secondary laparotomy for reconstruction of the continuity is not necessary. The anastomotic stoma can be performed in most regions of the small and large bowel.
    Type of Medium: Electronic Resource
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