ИССЛЕДОВАНИЕ ИЗНОСОСТОЙКОСТИ УПРОЧНЯЮЩИХ ПОКРЫТИЙ НА ИЗДЕЛИЯХ ИЗ СПЛАВА Д16Т

The paper provides results of investigations pertaining to wear resistance and friction characteristics of strengthening surfaces on the products made of D16T alloy in the process of sliding friction without lubricant material.Приводятся результаты исследования износостойкости и фрикционных характеристик упрочняющих покрытий на деталях из сплава Д16Т при трении скольжения без смазочного материала

ВЛИЯНИЕ ИОННОЙ ОБРАБОТКИ НА ИЗМЕНЕНИЕ ИСХОДНОЙ ШЕРОХОВАТОСТИ ПОВЕРХНОСТИ ОБРАЗЦОВ ИЗ СПЛАВА Д16Т

Results of the investigations pertaining to study of influence of technological ionic processing process parameters on changes in an initial roughness of samples made of D16Т alloy are provided in the paper.The paper shows that bombardment by high-energy Ti+-ions is effective at processing a surface with a high initial roughness and is not suitable for processing surfaces after grinding and polishing. It is necessary to use low-energy ions of inert gases for processing a surface with a low initial roughnessПриведены результаты исследования влияния технологических параметров процесса ионной обработки на изменение исходной шероховатости образцов из сплава Д16Т.Показано, что бомбардировка высокоэнергетическими ионами Ti+ эффективна при обработке поверхности с высокой исходной шероховатостью и непригодна для обработки поверхностей после шлифования и полирования. Для обработки поверхности с низкой исходной шероховатостью необходимо использовать низкоэнергетические ионы инертных газов.

Hydrogen absorption in thin ZnO films prepared by pulsed laser deposition

ZnO films with thickness of ~80 nm were grown by pulsed laser deposition (PLD) on MgO (1 0 0) single crystal and amorphous fused silica (FS) substrates. Structural studies of ZnO films and a high quality reference ZnO single crystal were performed by slow positron implantation spectroscopy (SPIS). It was found that ZnO films exhibit significantly higher density of defects than the reference ZnO crystal. Moreover, the ZnO film deposited on MgO substrate exhibits higher concentration of defects than the film deposited on amorphous FS substrate most probably due to a dense network of misfit dislocations. The ZnO films and the reference ZnO crystal were subsequently loaded with hydrogen by electrochemical cathodic charging. SPIS characterizations revealed that absorbed hydrogen introduces new defects into Zn

The `Parahippocampal Place Area' Responds Selectively to High Spatial Frequencies

Defining the exact mechanisms by which the brain processes visual objects and scenes remains an unresolved challenge. Valuable clues to this process have emerged from the demonstration that clusters of neurons (“modules”) in inferior temporal cortex apparently respond selectively to specific categories of visual stimuli, such as places/scenes. However, the higher-order “category-selective” response could also reflect specific lower-level spatial factors. Here we tested this idea in multiple functional MRI experiments, in humans and macaque monkeys, by systematically manipulating the spatial content of geometrical shapes and natural images. These tests revealed that visual spatial discontinuities (as reflected by an increased response to high spatial frequencies) selectively activate a well-known place-selective region of visual cortex (the “parahippocampal place area”) in humans. In macaques, we demonstrate a homologous cortical area, and show that it also responds selectively to higher spatial frequencies. The parahippocampal place area may use such information for detecting object borders and scene details during spatial perception and navigation.National Institutes of Health (U.S.) (NIH Grant R01 MH6752)National Institutes of Health (U.S.) (grant R01 EY017081)Athinoula A. Martinos Center for Biomedical ImagingNational Center for Research Resources (U.S.)Mind Research Institut

The F-box protein FBXO45 promotes the proteasome-dependent degradation of p73

The transcription factor p73, a member of the p53 family, mediates cell-cycle arrest and apoptosis in response to DNA damage-induced cellular stress, acting thus as a proapoptotic gene. Similar to p53, p73 activity is regulated by post-translational modification, including phosphorylation, acetylation and ubiquitylation. In C. elegans, the F-box protein FSN-1 controls germline apoptosis by regulating CEP-1, the single ancestral p53 family member. Here we report that FBXO45, the human ortholog of FSN-1, binds specifically to p73 triggering its proteasome-dependent degradation. Importantly, SCF(FBXO45) ubiquitylates p73 both in vivo and in vitro. Moreover, siRNA-mediated depletion of FBXO45 stabilizes p73 and concomitantly induces cell death in a p53-independent manner. All together, these results show that the orphan F-box protein FBXO45 regulates the stability of p73, highlighting a conserved pathway evolved from nematode to human by which the p53 members are regulated by an SCF-dependent mechanism