Classical osteosarcoma is one of the most common primary malignant bone tumors in children and adolescents. It more frequently occurs in the areas of the highest growth plate proliferation: limb long ...bones particularly in the distal femur (30%), proximal tibia (15%), and proximal humerus (15%). In the long bones, the tumor is located usually in the metaphysis (90%), less frequently in the diaphysis (9%), and very rarely in the epiphysis. This paper considers the clinical, radiological, and histological diagnosis, and prognosis in this pathology.
Binding of an amphiphilic dianion 1,5-bis(
p
-sulfonatophenyl)-3,7-diphenyl-1,5-diaza-3,7-diphosphacyclooctane (APCO
2−
) with an amphiphilic octacation tetra(methyl viologen) calix4resorcinol (MVCA
...8+
) in media containing different amounts of water and DMSO using NaClO
4
or NaCl as supporting electrolytes was shown for the first time by cyclic voltammetry and spectrophotometry. The stoichiometry of the complex depends on the MVCA
8+
: APCO
2−
ratio, medium, and supporting electrolyte. A 1: 1 charge-transfer complex is mainly formed (λ
max
= 480 nm) in 30% DMSO at a ratio of the compounds of 1: 1. A similar 1: 1 complex of APCO
2−
with a model compound methyl viologen MV
2+
(λ
max
= 482 nm) is formed under these conditions. A donor-acceptor interaction occurs between the acceptor viologen units and nitrogen-centered electron-donating fragments of the APCO
2−
dianion. An increase in the content of APCO
2−
in the solution leads to an additional binding of one (30 vol.% DMSO, water, NaClO
4
) or two (30 vol.% DMSO, water, NaCl) particles of APCO
2−
with the hydrophobic fragments of MVCA
8+
. The complexes aggregate to form insoluble precipitates in aqueous and water-DMSO media. A selective reversible electroswitching from the bound to free state of one of the three bound APCO
2−
particles was performed when reducing MVCA
8+
to MVCA
4·+
in a 30 vol.% DMSO/NaCl medium.
In experiments with Be mirrors bombarded by keV ions from a deuterium plasma a sharp drop of reflectance in the wavelength 220–650 nm was observed after quite low ion fluence although no mass loss of ...Be sample was measurable. Therefore such change of reflectance was ascribed to the transformation of the oxide layer, that naturally coats the Be mirror, into a hydroxide film. Supporting this hypothesis, the vacuum annealing of exposed samples at elevated temperature resulted in partial restoration of the reflectance. The effect of deuterium ion bombardment was closely related to the ion energy: the higher energy the deeper the drop of reflectance. In the paper we present results on the reflectance of Be mirrors depending on the experimental conditions, i.e., on the ion energy, annealing temperature, duration of exposure to bombardment by deuterium ions.
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