293 research outputs found
MECHANICAL CHAINS: IDENTIFICATION OF DYNAMICAL RESPONSES
Approaches for dynamical responses identification in example of system with three freedom degrees with tie between two of outside elements are offered. First approach bases on using of mathematical models-analogues of automation control theory, second approach bases on rules of transformation of design schemes of chains theory. Conversion from design schemes to equivalent in dynamical attitude of structural schemes of automation control is applied at using of structural method. Feedback tie in automation control system dedicated to the protection object is dynamical responses on external disturbance and at zero value of the disturbance disposed of the coerced elasticity of the system. The using of direct conversion of design schemes for the rules of chains theory shows identical results for both approaches
Small mammals in the upper belts of the Ural Mountains
Distribution of rodents in the upper belts of the Ural mountains In comparison with that in the lower belts and the adjacent plains Is reviewed based on the many year data obtained by the authors and taken from the literature.[es] Se revisa la distribución de los roedores en los pisos superiores de los Urales en comparación con la de los cinturones Inferiores y las llanuras adyacentes. Los resultados se basan en los datos obtenidos por los autores después de muchos años y en la información que aporta la bibliografÃa.
[fr] On revoit la distribution des rongeurs dans les étages supérieurs des monts Ourals en comparaison avec la distribution dans les étages inférieurs et les plaines adjacentes. Les résultats se sont appuyés dans les données obtenus par les auteurs après de beaucoup d'années de travail et dans l'information qu'apporte la bibliographie
Electrical characterization of top-gated molybdenum disulfide field-effect-transistors with high-k dielectrics
High quality HfO2 and Al2O3 substrates are fabricated in order to study their impact on top-gate MoS2 transistors. Compared with top-gate MoS2 FETs on a SiO2 substrate, the field effect mobility decreased for devices on HfO2 substrates but substantially increased for devices on Al2O3 substrates, possibly due to substrate surface roughness. A forming gas anneal is found to enhance device performance due to a reduction in charge trap density of the high-k substrates. The major improvements in device performance are ascribed to the forming gas anneal. Top-gate devices built upon Al2O3 substrates exhibit a near-ideal subthreshold swing (SS) of ~ 69 mV/dec and a ~ 10 × increase in field effect mobility, indicating a positive influence on top-gate device performance even without any backside bias
Polishing of Black and White CVD Grown Polycrystalline Diamond Coatings
Microwave plasma CVD growth can produce black and white varieties of polycrystalline diamond (PCD), depending on their as-grown purity. These two types of PCDs have been polished by mechanical and chemo-mechanical polishing respectively. It has been observed that initial roughness of 2.21μm for white PCD can be brought down to 175 nm after 70 hours of combined polishing, whereas, 85 hours of combined polishing could bring down the high initial roughness of 11.2μm for black PCD down to 546 nm at the end. Although, the material that was removed during polishing was higher for the black variety of PCD but it had lower polishing rate of 4nm/hr than white PCD (13nm/hr) during chemo-mechanical polishing. Such differential polishing rate was due to harder top polished surface of the black diamond than the white diamond. The nanoindentation study on the polished PCD surfaces revealed that the black PCD has a final nanohardness of 32.58±1 GPa whereas the white variety PCD had a polished surface nanohardness of 28.5±2 GPa. More conversion of diamond surface into harder amorphous sp3 than softer graphite during polishing action may have resulted such slow rate of anisotropic polishing for black diamond than white diamond
Threatening symbiosis of mass media and terrorism
Introduction. The terrorism - is a phenomenon always in dynamics,it has regularities in changes. The author of article considers symbiosis of mass media interference and terrorism transformation processes. Methods. The system structurally functional analysis and the content analysis constructed on qualitative and quantitative methods providing necessary representativeness and reliability of data became theoretical basis for the research. Results. Mass media had initial influence on growth of terrorism; it consists in symbiosis, and there are four modes of interaction between terrorists and mass media. Discussion. The contemporary history for the last decade has provided many examples of mutually beneficial relations between the terrorist organizations and mass media. On this perspective in domestic literature there are no developed tools which could give the commonly accepted definition of terrorism and measure its key parameters. This work can be used in case of developing the corresponding rates both for students of the Conflictology direction, and for professional development of law enforcement agencies employees course, the commissions of the Tatarstan Republic ATC
Beam instrumentation for the Tevatron Collider
The Tevatron in Collider Run II (2001-present) is operating with six times
more bunches and many times higher beam intensities and luminosities than in
Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and
the never-ending luminosity upgrade campaign. We present the overall picture of
the Tevatron diagnostics development for Run II, outline machine needs for new
instrumentation, present several notable examples that led to Tevatron
performance improvements, and discuss the lessons for future colliders
Probing interface defects in top-gated MoS2 transistors with impedance spectroscopy
The electronic properties of the HfO2/MoS2 interface were investigated using multifrequency capacitance–voltage (C–V) and current–voltage characterization of top-gated MoS2 metal–oxide–semiconductor field effect transistors (MOSFETs). The analysis was performed on few layer (5–10) MoS2 MOSFETs fabricated using photolithographic patterning with 13 and 8 nm HfO2 gate oxide layers formed by atomic layer deposition after in-situ UV-O3 surface functionalization. The impedance response of the HfO2/MoS2 gate stack indicates the existence of specific defects at the interface, which exhibited either a frequency-dependent distortion similar to conventional Si MOSFETs with unpassivated silicon dangling bonds or a frequency dispersion over the entire voltage range corresponding to depletion of the HfO2/MoS2 surface, consistent with interface traps distributed over a range of energy levels. The interface defects density (Dit) was extracted from the C–V responses by the high–low frequency and the multiple-frequency extraction methods, where a Dit peak value of 1.2 × 1013 cm–2 eV–1 was extracted for a device (7-layer MoS2 and 13 nm HfO2) exhibiting a behavior approximating to a single trap response. The MoS2 MOSFET with 4-layer MoS2 and 8 nm HfO2 gave Dit values ranging from 2 × 1011 to 2 × 1013 cm–2 eV–1 across the energy range corresponding to depletion near the HfO2/MoS2 interface. The gate current was below 10–7 A/cm2 across the full bias sweep for both samples indicating continuous HfO2 films resulting from the combined UV ozone and HfO2 deposition process. The results demonstrated that impedance spectroscopy applied to relatively simple top-gated transistor test structures provides an approach to investigate electrically active defects at the HfO2/MoS2 interface and should be applicable to alternative TMD materials, surface treatments, and gate oxides as an interface defect metrology tool in the development of TMD-based MOSFETs
Vimentin is a novel AKT1 target mediating motility and invasion.
The PI3K/AKT signaling pathway is aberrant in a wide variety of cancers. Downstream effectors of AKT are involved in survival, growth and metabolic-related pathways. In contrast, contradictory data relating to AKT effects on cell motility and invasion, crucial prometastatic processes, have been reported pointing to a potential cell type and isoform type-specific AKT-driven function. By implication, study of AKT signaling should optimally be conducted in an appropriate intracellular environment. Prognosis in soft-tissue sarcoma (STS), the aggressive malignancies of mesenchymal origin, is poor, reflecting our modest ability to control metastasis, an effort hampered by lack of insight into molecular mechanisms driving STS progression and dissemination. We examined the impact of the cancer progression-relevant AKT pathway on the mesenchymal tumor cell internal milieu. We demonstrate that AKT1 activation induces STS cell motility and invasiveness at least partially through a novel interaction with the intermediate filament vimentin (Vim). The binding of AKT (tail region) to Vim (head region) results in Vim Ser39 phosphorylation enhancing the ability of Vim to induce motility and invasion while protecting Vim from caspase-induced proteolysis. Moreover, vimentin phosphorylation was shown to enhance tumor and metastasis growth in vivo. Insights into this mesenchymal-related molecular mechanism may facilitate the development of critically lacking therapeutic options for these devastating malignancies
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