Zirconium and hafnium oxide interface with silicon: Computational study of stress and strain effects

Computations of the periodic double-interface MO₂/Si (M = Zr and Hf) systems using density functional theory (DFT) demonstrate that very thin epitaxial MO₂ layers at silicon (1 0 0) surface adopt anatase-like structure with six-coordinate M atoms, while tetragonal-like MO₂ structure with seven-coordinated M atoms has a lower stability (metastable). This results from a closer match between Si(1 0 0) surface unit cell and anatase-like ZrO₂ and HfO₂ leading to the overall stress reduction if MO₂ adopts the anatase-like structure on silicon. In agreement with the previous study of Gavartin et al. [Gavartin, Fonseca, Bersuker, Shluger, Microelectron. Eng. 80 (2005) 412–415] formation of oxygen vacancy at the interface is demonstrated to be lower than in bulk film. This result appears to be independent from the film or interface structure but originates from the energy balance between M–O, M–M, Si–O and M–Si bonds, as revealed by a simple molecular model.     

Up-milling and down-milling wood with different grain orientations – the cutting forces behaviour

Peripheral milling of wood with up milling and down milling techniques is very well known from a geometrical point of view. However, in processing anisotropic materials such as wood, these geometrical aspects imply relevant differences when machining. In fact, milling of anisotropic material leads to different cutting geometries when up- or down-milling and when increasing or decreasing the depth of cut resulting in different grain orientations depending on the adopted process. In this paper, tests performed when processing Douglas Fir with different depths of cut and grain orientations are described. The cutting forces were measured, and the dependence of the cutting forces with respect on the cutting geometry are analysed and discussed.     

Laser irradiation of ZnO:Al/Ag/ZnO:Al multilayers for electrical isolation in thin film photovoltaics

Laser irradiation of ZnO:Al/Ag/ZnO:Al transparent contacts is investigated for segmentation purposes. The quality of the irradiated areas has been experimentally evaluated by separation resistance measurements, and the results are complemented with a thermal model used for numerical simulations of the laser process. The presence of the Ag interlayer plays two key effects on the laser scribing process by increasing the maximum temperature reached in the structure and accelerating the cool down process. These evidences can promote the use of ultra-thin ZnO:Al/Ag/ZnO:Al electrode in large-area products, such as for solar modules.     

Effects of enantiomeric solvents on the activity, thermostability and activation energy of lipoprotein lipase

The kinetic parameters (K_m and V_max) of lipoprotein lipase (LPL)-catalyzed transesterification were determined in (R)- and (S)-carvone, and in mixtures of the two. It was found that only V_max was significantly affected by solvent chirality. LPL thermostability was not influenced by solvent config- uration, whereas activation energy was twice as high in (R)-carvone as in (S)-carvone.     

Toward the Development of Dual‐Targeted Glyceraldehyde‐3‐phosphate Dehydrogenase/Trypanothione Reductase Inhibitors against Trypanosoma brucei and Trypanosoma cruzi

A significant improvement in the treatment of trypanosomiases has been achieved with the recent development of nifurtimox–eflornithine combination therapy (NECT). As an alternative to drug combinations and as a means to overcome most of the antitrypanosomatid drug discovery challenges, a multitarget drug design strategy has been envisaged. To begin testing this hypothesis, we designed and developed a series of quinone–coumarin hybrids against glyceraldehyde‐3‐phosphate dehydrogenase/trypanothione reductase (GAPDH/TR). These enzymes belong to metabolic pathways that are vital to Trypanosoma brucei and Trypanosoma cruzi, and have thus been considered promising drug targets. The synthesized molecules were characterized for their dual‐target antitrypanosomal profile, both in enzyme assays and in in vitro parasite cultures. The merged derivative 2‐{[3‐(3‐dimethylaminopropoxy)‐2‐oxo‐2H‐chromen‐7‐yl]oxy}anthracene‐1,4‐dione ( 10 ) showed an IC₅₀ value of 5.4 μM against TbGAPDH and a concomitant K_i value of 2.32 μM against TcTR. Notably, 2‐{4‐[6‐(2‐dimethylaminoethoxy)‐2‐oxo‐2H‐chromen‐3‐yl]phenoxy}anthracene‐1,4‐dione (compound 6 ) displayed a remarkable EC₅₀ value for T. brucei parasites (0.026 μM ) combined with a very low cytotoxicity toward mammalian L6 cells (7.95 μM ). This promising low toxicity of compound 6 might be at least partially due to the fact that it does not interfere with human glutathione reductase.     

Evaluation of electromagnetic power deposition in a spherical multilayer head in the near field of a linear antenna

The canonical problem of the radiation of an elementary dipole close to a stratified sphere representing a simplified model of human head is investigated in this paper. The proposed approach is a flexible method of investigation about the influence on Specific Absorption Rate (S.A.R.) evaluation of tissue dielectric parameters and geometry as well as a useful tool to test numerical codes. The solution of the electromagnetic (e.m.) problem is achieved in a closed form; results highlight the position of maximum S.A.R. values and their dependence on frequency: for particular layer thicknesses and dielectric parameters, the maximum absorption can occur in the frequency range of cellular phones.     

GFAP, S-100 and vimentin proteins in rat after cerebral post-ischemic reperfusion

Mutation of the TP53 gene is one of the most common molecular alterations in a variety of tumors, but it occurs infrequently in childhood and adult hematological malignancies. Protein accumulation often results from mutations that lead to inactivation of the p53 protein. Other causes of functional inactivation of the p53 protein include stabilization of p53 via proteins such as MDM2, an oncoprotein capable of forming specific complexes with p53. In the present study, protein expressions of MDM2 and p53 were investigated by immunohistochemistry from bone marrow samples in 23 patients with acute lymphoblastic leukemia aged 1-13 years at diagnosis. p53 protein overexpression was detected in only one case, while overexpression of MDM2 was detected in samples from five patients. All five patients overexpressing MDM2 belonged to a group with unfavorable prognostic signs at diagnosis and three of them relapsed or died within 6 months after diagnosis.     

Monoazo dyes for polyamide derived from 4-alkylamido-2-hydroxybenzoic acids

Data on a series of 65 azo dyes derived from 4-alkylamido-2-hydroxybenzoic acids are reported. The dyes are suitable for application to polyamide fibres.Many correlations between the nature of substituents and the physical, spectroscopic or tinctorial properties of dyes were established. Correlations between structure and colour of dyed fabrics were also found.