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91.
Enik Szkely Gizella Csire Bettina Dina Balogh Judit Zsuzsa Erdei Judit Mria Kirly Judit Kocsi Júlia Pinkczy Katalin Vrnagy 《Molecules (Basel, Switzerland)》2022,27(11)
The systematic studies of copper(II), nickel(II) and zinc(II) ion complexes of protected multihistidine peptides containing amino acids with different side chains (Ac-SarHAH-NH2, Ac-HADH-NH2, Ac-HDAH-NH2, Ac-HXHYH-NH2 X, Y = A, F, D or K, Ac-HXHAHXH-NH2, X = F or D) have provided information about the metal ion and protein interaction and have made it possible to draw conclusions regarding general trends in the coordination of metal complexes of multihistidine peptides. The stability of the metal complexes significantly depends on the position of the histidines and amino acids, which are present in the neighbourhood of the histidine amino acids as well. The most significant effect was observed on peptides containing aspartic acid or phenylalanine. The redox parameters of complexes, however, depend on the number and position of histidines, and the other side chain donor atoms have practically no effect on the electrochemical properties of imidazole-coordinated species. However, the presence of aspartic acid side chains results in a more distorted geometry of amide-coordinated species and increases the reducibility of these complexes. 相似文献
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Oswin Aichholzer Franz Aurenhammer Thomas Hackl Bettina Speckmann 《Computational Geometry》2009,42(6-7):627-631
In this note we discuss some structural properties of minimum weight pseudo-triangulations of point sets. 相似文献
94.
Robert Kandlbinder Robert Schupfner Otto S. Wolfbeis Bettina Zinka 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(2):187-192
The incorporation of naturally occurring thorium isotopes in human femur bones was studied by analyzing 28 bone samples. The
results show that the activity concentrations of 232Th and 230Th are in the range of the blank values resulting in an upper limit of theirs activity concentrations in human bones. The
presence of 228Th can be attributed, on the basis of model calculations, to the radioactive decay of deposited 228Ra. We conclude that thorium is not detectably incorporated into human bones. 相似文献
95.
Sugar–Edge Interactions in a DNA–RNA G‐Quadruplex: Evidence of Sequential C−H⋅⋅⋅O Hydrogen Bonds Contributing to RNA Quadruplex Folding
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Jonathan Dickerhoff Dr. Bettina Appel Prof. Dr. Sabine Müller Prof. Dr. Klaus Weisz 《Angewandte Chemie (International ed. in English)》2016,55(48):15162-15165
DNA G‐quadruplexes were systematically modified by single riboguanosine (rG) substitutions at anti‐dG positions. Circular dichroism and NMR experiments confirmed the conservation of the native quadruplex topology for most of the DNA–RNA hybrid structures. Changes in the C8 NMR chemical shift of guanosines following rG substitution at their 3′‐side within the quadruplex core strongly suggest the presence of C8?H???O hydrogen‐bonding interactions with the O2′ position of the C2′‐endo ribonucleotide. A geometric analysis of reported high‐resolution structures indicates that such interactions are a more general feature in RNA quadruplexes and may contribute to the observed preference for parallel topologies. 相似文献
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98.
Mihály Hujter Bettina Klinz Gerhard J. Woeginger 《Mathematical Methods of Operations Research》1999,50(1):9-16
In this note we investigate the computational complexity of the transportation problem with a permutable demand vector, TP-PD for short. In the TP-PD, the goal is to permute the elements of the given integer demand vector b=(b1,
,bn) in order to minimize the overall transportation costs. Meusel and Burkard [6] recently proved that the TP-PD is strongly NP-hard. In their NP-hardness reduction, the used demand values bj, j=1,
,n, are large integers. In this note we show that the TP-PD remains strongly NP-hard even for the case where bj]{0,3} for j=1,
,n. As a positive result, we show that the TP-PD becomes strongly polynomial time solvable if bj] {0,1,2} holds for j=1,
,n. This result can be extended to the case where bj]{3,3+1,3+2} for an integer 3. 相似文献
99.