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61.
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Karl-Heinz Jansen 《Mathematische Annalen》1969,183(3):185-200
Ohne Zusammenfassung 相似文献
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The authors use a Q-switched laser for the vaporization and ionization of sample materials. The ions thus formed are separated according to energy and mass-charge ratio and finally detected with a double-focusing mass spectrometer. It is shown that this method permits semiquantitative analysis of both conducting and non-conducting inorganic materials, without the use of reference samples. The samples may be in the form of solid, powdered or liquid bulk materials, thin layers, deposits or inclusions. 相似文献
67.
BACKGROUND: Human papillomaviruses (HPV) are the most common sexually transmitted viruses. Infection of the cervical epithelium by HPVs can lead to the development of cervical cancer. Recent advances in vaccine research have shown that immunization with papillomavirus-like particles (VLPs) containing the major structural viral protein, L1 from HPV 16 can provide protection from the establishment of a chronic HPV 16 infection and related cervical intraepithelial neoplasia (CIN) in baseline HPV 16 naive women. METHODS: To better understand the quantitative and qualitative effects of aluminum adjuvant on the immunogenic properties of an HPV 6, 11, 16 and 18L1 VLP vaccine, we used an HPV-specific, antibody isotyping assay and a competitive immunoassay that measures antibodies to neutralizing epitopes to profile sera from rhesus macaques immunized with the HPV L1 VLP vaccine formulated with or without aluminum adjuvant. RESULTS: Immunization with VLPs formulated with the aluminum adjuvant elicited a significantly stronger immune response with higher peak antibody titers both at four weeks post vaccination (12.7 to 41.9-fold higher) as well as in the persistent phase at week 52 (4.3 to 26.7-fold higher) than that of VLPs alone. Furthermore, the aluminum adjuvant formulated HPV VLP vaccine elicited a predominantly T helper type 2 response, with high levels of IgG1 and IgG4 and low levels of IgG2. The vaccine also elicited high levels of serum IgA, which may be important in providing mucosal immunity to impart protection in the anogenital tract. CONCLUSION: These results show that the HPV 6, 11, 16 and 18 L1-VLP vaccine formulated with Merck aluminum adjuvant elicits a robust and durable immune response and holds promise as a vaccine for preventing cervical cancer. 相似文献
68.
We report the synthesis of novel edge-sharing chain systems Na(3)Cu(2)O(4) and Na(8)Cu(5)O(10), which form insulating states with commensurate charge order. We identify these systems as one-dimensional Wigner lattices, where the charge order is determined by long-range Coulomb interaction and the number of holes in the d shell of Cu. Our interpretation is supported by x-ray structure data as well as by an analysis of magnetic susceptibility and specific heat data. Remarkably, due to large second neighbor Cu-Cu hopping, these systems allow for a distinction between the (classical) Wigner lattice and the 4k(F) charge-density wave of quantum mechanical origin. 相似文献
69.
We observe pronounced transport anisotropies in magnetotransport experiments performed in the two-dimensional electron system of a Si/SiGe heterostructure. They occur when an in-plane field is used to tune two Landau levels with opposite spin to energetic coincidence. The observed anisotropies disappear drastically for temperatures above 1 K. We propose that our experimental findings may be caused by the formation of a unidirectional stripe phase oriented perpendicular to the in-plane field. 相似文献
70.
In this paper the main focus is on a stability concept for solutions of a linear complementarity problem. A solution of such
a problem is robust if it is stable against slight perturbations of the data of the problem. Relations are investigated between
the robustness, the nondegenerateness and the isolatedness of solutions. It turns out that an isolated nondegenerate solution
is robust and also that a robust nondegenerate solution is isolated. Since the class of linear complementarity problems with
only robust solutions or only nondegenerate solutions is not an open set, attention is paid to Garcia's classG
n
of linear complementarity problems. The nondegenerate problems inG
n
form an open set. 相似文献