Calculation of thermal parameters of SiGe microbolometers

The thermal parameters of a SiGe microbolometer were calculated using numerical modeling. The calculated thermal conduction and thermal response time are in good agreement with the values found experimentally and range between 2x10$^-7$ and 7x10$^-8$ W/K and 1.5 and 4.5 ms, respectively. High sensitivity of microbolometer is achieved due to optimization of the thermal response time and thermal conduction by fitting the geometry of supporting heat-removing legs or by selection of a suitable material providing boundary thermal resistance higher than 8x10$^-3$ cm$^2$K/W at the SiGe interface.Comment: 11 pages, 6 figure

Bacillus intermedius ribonuclease (BINASE) induces apoptosis in human ovarian cancer cells

© 2014 Elsevier B.V. All rights reserved. The cytotoxic effects of Bacillus intermedius RNase (binase) towards ovarian cancer cells (SKOV3 and OVCAR5) were studied in comparison to normal ovarian epithelial cells (HOSE1 and HOSE2). Binase decreased viability and induced the selective apoptosis of ovarian cancer cells. The apoptosis rate was 50% in SKOV3 and 48% in OVCAR5 cells after 24 h of binase treatment (50 μg/ml). Binase-induced apoptosis in these cell lines was accompanied by caspase-3 activation and poly(ADP-ribose) polymerase fragmentation. Normal ovarian epithelial cells were not affected by binase, except for a slight decrease of HOSE2 cell viability and the appearance of traces of activated caspase-3, but not the poly(ADP-ribose) polymerase 85-kDA fragment. Binase did not induce alteration of EZH2 (enhancer of zeste-homolog-2) protein expression neither, in tumor nor in normal cells. In conclusion, selective binase-induced cell death and apoptosis via poly(ADP-ribose) polymerase fragmentation may serve as a new treatment option against ovarian cancer progression

Influence of plasma volume discharge in atmospheric-pressure air on the admittance of MIS structures based on MBE p-HgCdTe

This article investigates the effect of a nanosecond plasma volume discharge, which is formed in an inhomogeneous electrical field at atmospheric pressure, on the electrical properties of MIS structures based on HgCdTe (MCT) epitaxial films. The MIS structure based on films exposed to the discharge significantly changed its main parameters. The most notable feature of the structure exposed to discharge is the significant increase in the positive fixed charge in the insulator. A possible reason for changes in the characteristics of MIS structure after exposure to discharge is the significant change in the impurity-defect system of the semiconductor near the interface. This is accompanied with a formation of an insulator film of nanometer thickness on the surface, which gives rise to positive fixed charge

Recent Advances and Future Direction in Lyophilisation and Desiccation of Mesenchymal Stem Cells

© 2016 Akalabya Bissoyi et al.Mesenchymal Stem Cells (MSCs) are a promising mammalian cell type as they can be used for the reconstruction of human tissues and organs. MSCs are shown to form bone, cartilage, fat, and muscle-like cells under specific cultivation conditions. Current technology of MSCs cryopreservation has significant disadvantages. Alternative technologies of mammalian cells preservation through lyophilisation or desiccation (air-drying) are among the upcoming domains of investigation in the field of cryobiology. Different protectants and their combinations were studied in this context. Loading of the protectant in the live cell can be a challenging issue but recent studies have shown encouraging results. This paper deals with a review of the protectants, methods of their delivery, and physical boundary conditions adopted for the desiccation and lyophilisation of mammalian cells, including MSCs. A hybrid technique combining both methods is also proposed as a promising way of MSCs dry preservation

Influence of pulsed nanosecond volume discharge in atmospheric-pressure air on the electrical characteristics of MCT epitaxial films

The purpose of this paper was investigating the effect of volume nanosecond discharge in air at atmospheric pressure on the electro-physical properties of the HgCdTe (MCT) epitaxial films grown by molecular beam epitaxy. Hall measurements of electro-physical parameters of MCT samples after irradiation have shown that there is a layer of epitaxial films exhibiting n-type conductivity that is formed in the near-surface area. After more than 600 pulses of influence parameters and thickness of the resulting n-layer is such that the measured field dependence of Hall coefficient corresponds to the material of n-type conductivity. Also it is shown that the impact of the discharge leads to significant changes in electro-physical characteristics of MIS structures. This fact is demonstrated by increase in density of positive fixed charge, change in the hysteresis type of the capacitance-voltage characteristic, an increase in density of surface states. The preliminary results show that it is possible to use such actions in the development of technologies of the controlled change in the properties of MCT. © (2015) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only

Admittance investigation of MIS structures with GgTe-based single quantum wells

This work presents results of the investigation of admittance of metal-insulator-semiconductor structure based on Hg1 − xCdxTe grown by molecular beam epitaxy. The structure contains a single quantum well Hg0.35Cd0.65Te/HgTe/Hg0.35Cd0.65Te with thickness of 5.6 nm in the sub-surface layer of the semiconductor. Both the conductance-voltage and capacitance-voltage characteristics show strong oscillations when the metal-insulator-semiconductor (MIS) structure with a single quantum well based on HgTe is biased into the strong inversion mode. Also, oscillations on the voltage dependencies of differential resistance of the space charge region were observed. These oscillations were related to the recharging of quantum levels in HgTe

Unipolar barrier structures based on HgCdTe for infrared detection

One of the topical areas of solid state photoelectronics is the creation of infrared detectors based on unipolar barrier systems (for example, with an nBn architecture). The greatest progress has been achieved in the development of barrier detectors based on semiconductors of the AIIIBV group, which is associated with the possibility of realizing systems with a zero barrier in the valence band. Unipolar barrier detectors based on mercury cadmium telluride (HgCdTe) grown by molecular beam epitaxy (MBE) are of interest due to significant technological advantages, since the creation of such devices can abandon the defect forming procedure of ion implantation. Despite a significant number of theoretical works, only a few attempts are known to practically implement nBn detectors based on MBE HgCdTe

New Antioxidant Genes from an Anhydrobiotic Insect: Unique Structural Features in Functional Motifs of Thioredoxins

© 2016, Springer Science+Business Media New York.Polipedilum vanderplanki is the most complex known organism able to survive body desiccation via entering a state of suspended metabolism called anhydrobiosis. This unique ability is based on the specific molecular machinery involving a synthesis of non-reducing sugar trehalose and a variety of protective proteins. Genes encoding these protective proteins are extensively duplicated in the P. vanderplanki genome and become hugely upregulated in response to desiccation. Some of these highly expressed genes encode substitutions of amino acids crucial for the function of corresponding proteins. An intriguing group of protective proteins in P. vanderplanki are thioredoxins (TRX). These antioxidant proteins are important for P. vanderplanki anhydrobiosis since desiccation is tightly related to the elevated production of free radicals and oxidative damage. The TRX set is unprecedentedly expanded in the P. vanderplanki genome up to 25 TRX genes. Genomes of congeneric midge Polipedilum nubifer, Apis mellifera, Drosophila melanogaster, and Anopheles gambiae encode only 3–7 TRX genes. Moreover, all three P. vanderplanki thioredoxin genes most expressed at 24 h of P. vanderplanki larva desiccation encode for proteins missing the typical CxxC motif