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331.
332.
Gabor Toth 《Geometriae Dedicata》2009,143(1):69-80
Asymmetry of a compact convex body L ì Rn{\mathcal L \subset {\bf R}^n} viewed from an interior point O{\mathcal O} can be measured by considering how far L{\mathcal L} is from its inscribed simplices that contain O{\mathcal O}. This leads to a measure of symmetry s(L, O){\sigma(\mathcal L, \mathcal O)}. The interior of L{\mathcal L} naturally splits into regular and singular sets, where the singular set consists of points O{\mathcal O} with largest possible s(L, O){\sigma(\mathcal L, \mathcal O)}. In general, to calculate the singular set of a compact convex body is difficult. In this paper we determine a large subset
of the singular set in centrally symmetric compact convex bodies truncated by hyperplane cuts. As a function of the interior
point O{\mathcal O}, s(L, .){\sigma(\mathcal L, .)} is concave on the regular set. It is natural to ask to what extent does concavity of s(L, .){\sigma(\mathcal L, .)} extend to the whole (interior) of L{\mathcal L}. It has been shown earlier that in dimension two, s(L, .){\sigma(\mathcal L, .)} is concave on L{\mathcal L}. In this paper, we show that in dimensions greater than two, for a centrally symmetric compact convex body L{\mathcal L}, s(L, .){\sigma(\mathcal L, .)} is a non-concave function provided that L{\mathcal L} has a codimension one simplicial intersection. This is the case, for example, for the n-dimensional cube, n ≥ 3. This non-concavity result relies on the fact that a centrally symmetric compact convex body has no regular points. 相似文献
333.
Gabor Borzsonyi Martins S. Oderinde Rachel L. Beingessner Bo‐Liang Deng Takeshi Yamazaki Robert McDonald Andriy Kovalenko Hicham Fenniri 《Helvetica chimica acta》2009,92(10):1963-1972
Four heterocyclic compounds are presented which exhibit specific self‐recognition of identical Donor–Acceptor (D–A) H‐bonding arrays, resulting in solid‐state tapes with the same, but anti‐parallel functional‐group distribution on opposite sides. A detailed X‐ray‐crystallographic analysis of these supramolecular structures is described. 相似文献
334.
Gabor Jarvas Dora Szerenyi Jozsef Tovari Laszlo Takacs Andras Guttman 《Molecules (Basel, Switzerland)》2021,26(16)
Background: It is well known that more than 90% of cancer deaths are due to metastases. However, the entire tumorigenesis process is not fully understood, and it is evident that cells spreading from the primary tumor play a key role in initiating the metastatic process. Tumor proliferation and invasion also elevate the concentration of regular and irregular metabolites in the serum, which may alter the normal function of the entire human homeostasis and possibly causes cancer metabolism syndrome, also referred to as cachexia. Methods: We report on the modification of commercially available hemodialysis membranes to selectively capture circulating tumor cells from the blood stream by means of immobilized human anti-EpCAM antibodies on the inner surface of the fibers. All critical steps are described that required in situ addition of the immuno-affinity feature to hemodialyzer cartridges in order to capture EpCAM positive circulating tumor cells, which represents ~80% of cancer cell types. Results: The cell capture efficiency of the suggested technology was demonstrated by spiking HCT116 cancer cells both into buffer solution and whole blood and run through on the modified cartridge. Flow cytometry was used to quantitatively evaluate the cell clearance performance of the approach. Conclusions: The suggested modification has no significant effect on the porous structure of the hemodialysis membranes; it keeps its cytokine removal capability, addressing cachexia simultaneously with CTC removal. 相似文献
335.
Pim van der Hoorn Gabor Lippner Dmitri Krioukov 《Journal of statistical physics》2018,173(3-4):806-844
Even though power-law or close-to-power-law degree distributions are ubiquitously observed in a great variety of large real networks, the mathematically satisfactory treatment of random power-law graphs satisfying basic statistical requirements of realism is still lacking. These requirements are: sparsity, exchangeability, projectivity, and unbiasedness. The last requirement states that entropy of the graph ensemble must be maximized under the degree distribution constraints. Here we prove that the hypersoft configuration model, belonging to the class of random graphs with latent hyperparameters, also known as inhomogeneous random graphs or W-random graphs, is an ensemble of random power-law graphs that are sparse, unbiased, and either exchangeable or projective. The proof of their unbiasedness relies on generalized graphons, and on mapping the problem of maximization of the normalized Gibbs entropy of a random graph ensemble, to the graphon entropy maximization problem, showing that the two entropies converge to each other in the large-graph limit. 相似文献
336.
Stoian Sergiu Alexandru Gabor Augusta Raluca Albu Ana-Maria Nicolae Cristian Andi Raditoiu Valentin Panaitescu Denis Mihaela 《Journal of Thermal Analysis and Calorimetry》2019,138(4):2469-2480
Journal of Thermal Analysis and Calorimetry - Polypropylene (PP) is a versatile polymer, with a wide range of applications, from household appliances to packaging and automotive components.... 相似文献
337.
We propose public-key encryption algorithms based on chaotic maps, which are generalization of well-known and commercially used algorithms: Rivest-Shamir-Adleman (RSA), ElGamal, and Rabin. For the case of generalized RSA algorithm we discuss in detail its software implementation and properties. We show that our algorithm is as secure as RSA algorithm. 相似文献
338.
339.
340.
Gábor?SzalontaiEmail author Gábor?Besenyei 《Monatshefte für Chemie / Chemical Monthly》2005,136(5):663-676
Summary. Straightforward 31P MAS investigations were carried out in the solid state on a series of [Pd2X2(dppm)2] (X=Cl, Br, I) complexes in order to study the effects that ring distortion, conformations, and crystal packing have on the solid-state spectra of these molecules and also to get experimental values for certain scalar couplings (e.g. two-bond trans P–Pd–P) normally not available from solution-state spectra.The phosphorus nuclei in these structures form a tightly dipolar coupled four-spin system which cannot be treated by the averaged Hamiltonian theory. The presence of strong homonuclear dipolar couplings, especially under the so called rotational resonance conditions, was expected to add to the complexity of the spectra. It turned out that the molecules are asymmetric in solid state but the rotation-rate dependence of the spectra is simpler than expected. Whereas trans spin-pairs with small isotropic chemical shift differences show a J-recouping phenomenon at modest MAS frequencies, the strongly dipolar coupled cis pairs (outside of the real rotational resonance conditions) do not have a characteristic effect in the rotation range studied or the effect is beyond the spectral resolution (<250Hz). At higher MAS frequencies under the assumption of inhomogeneous behaviour reliable values of the trans J-couplings are available from the spectra. 相似文献