Thickness Dependent Growth of Epitaxial Iron Silicide Nanoobjects on Si (001)

Strain-induced, self-assembled iron silicide nanostructures were grown on Si(001) substrate by conventional Fe evaporation and subsequent annealing. The initial Fe thickness was in the 0.1-6.0 nm range and the annealing temperature was 850 °C. The formed phases and structures were characterized by reflection high energy electron diffraction, and scanning electron microscopy. The electrical characteristics were investigated by I-V and C-V measurements, and by DLTS. The samples show silicide nanostructure formation in the whole thickness range. The shape of the nanostructures varied from rod like to triangular and quadratic depending on the initial Fe thickness. The size distribution of the formed iron silicide nanoobjects was not homogeneous, but they were oriented in square directions on Si(001). Higher thickness resulted in increased particles size. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3518

Carboxypeptidase-M is regulated by lipids and CSFs in macrophages and dendritic cells and expressed selectively in tissue granulomas and foam cells

Granulomatous inflammations, characterized by the presence of activated macrophages (MAs) forming epithelioid cell (EPC) clusters, are usually easy to recognize. However, in ambiguous cases the use of a MA marker that expresses selectively in EPCs may be needed. Here, we report that carboxypeptidase-M (CPM), a MA-differentiation marker, is preferentially induced in EPCs of all granuloma types studied, but not in resting MAs. As CPM is not expressed constitutively in MAs, this allows utilization of CPM-immunohistochemistry in diagnostics of minute granuloma detection when dense non-granulomatous MAs are also present. Despite this rule, hardly any detectable CPM was found in advanced/active tubercle caseous disease, albeit in early tuberculosis granuloma, MAs still expressed CPM. Indeed, in vitro both the CPM-protein and -mRNA became downregulated when MAs were infected with live mycobacteria. In vitro, MA-CPM transcript is neither induced remarkably by interferon-γ, known to cause classical MA activation, nor by IL-4, an alternative MA activator. Instead, CPM is selectively expressed in lipid-laden MAs, including the foam cells of atherosclerotic plaques, xanthomatous lesions and lipid pneumonias. By using serum, rich in lipids, and low-density lipoprotein (LDL) or VLDL, CPM upregulation could be reproduced in vitro in monocyte-derived MAs both at transcriptional and protein levels, and the increase is repressed under lipid-depleted conditions. The microarray analyses support the notion that CPM induction correlates with a robust progressive increase in CPM gene expression during monocyte to MA maturation and dendritic cell (DC) differentiation mediated by granulocyte–MA-colony-stimulating factor+IL-4. M-CSF alone also induced CPM. These results collectively indicate that CPM upregulation in MAs is preferentially associated with increased lipid uptake, and exposure to CSF, features of EPCs, also. Therefore, CPM-immunohistochemistry is useful for granuloma and foam MA detections in tissue sections. Furthermore, the present data offer CPM for the first time to be a novel marker and cellular player in lipid uptake and/or metabolism of MAs by promoting foam cell formation

Effect of dislocations in relaxed MBE SiGe layers on the electrical behavior of Si/SiGe heterostructures

Defects in Si/SiGe heterostructures and electrical behavior thereof have been studied. Misfit dislocations were observed in the epitaxial layers using cross-sectional transmission electron microscopy. These defects cause anomalies in the electrical behavior. It has been shown that, in spite of anomalies, the electrical measurements provide useful and reliable information on the structures.Исследованы дефекты в гетероструктурах Si/SiGe и их электрические характеристики. В эпитаксиальных слоях методом просвечивающей электронной микроскопии поперечных сечений обнаружены дислокации несоответствия. Эти дефекты вызывают аномалии в электрических характеристиках. Показано, что, несмотря на эти аномалии, электрические измерения обеспечивают полезную и надежную информацию о структурах.Досліджєно дефекти у гетероструктурах Si/SiGe та їх єлєктричні характеристики. В епітаксиальних шарах методом просвічувальної електронної мікроскопії поперечних перерізів виявлено дислокації невідповідності. Ці дефекти спричиняють аномалії в електричних характеристиках. Показано, що, незважаючи на ці аномалії, електричні вимірювання забезпечують корисну та надійну інформацію про структури