Vertical nanowire/nanosheet FETs with a horizontal channel for threshold voltage modulation

A new type of vertical nanowire (VNW)/nanosheet (VNS) FETs combining a horizontal channel (HC) with bulk/back-gate electrode configuration, including Bulk-HC and FD-SOI-HC VNWFET, is proposed and investigated by TCAD simulation. Comparisons were carried out between conventional VNWFET and the proposed devices. FD-SOI-HC VNWFET exhibits better I on/I off ratio and DIBL than Bulk-HC VNWFET. The impact of channel doping and geometric parameters on the electrical characteristic and body factor (γ) of the devices was investigated. Moreover, threshold voltage modulation by bulk/back-gate bias was implemented and a large γ is achieved for wide range V th modulation. In addition, results of I on enhancement and I off reduction indicate the proposed devices are promising candidates for performance and power optimization of NW/NS circuits by adopting dynamic threshold voltage management. The results of preliminary experimental data are discussed as well.

The Development Problems of Two-Fuel Burner for the Gas Turbine Combustion Chamber

The work is devoted to the design of a spraying device for the combustion chamber GTE-65.1 on liquid fuel. The paper presents the following results: 1) The 3D calculations of the air channels characteristics for two burners types — pilot and main — were carried out. Data were obtained on the flow and pressure fields inside and at the burners outlet, and also the volumes of the reverse flow zones. 2) The main and pilot nozzles have been designed for the two spraying devices types. The values of droplet dispersity and spray angle were obtained, depending on the fuel injection pressure. 3) Based on the calculations carried out, the models of two spraying liquid fuel devices were designed and manufactured, the design of which is based on the design of the single-fuel combustion chamber (CC) on natural gas burners for GTE-65.1. At the next stage of the work, it is planned to carry out experimental studies of the two devices models aimed at obtaining an aerosol mixture with the desired properties to ensure uninterrupted operation of the GTE-65.1 on liquid fuel. Some preliminary experimental data are presented in this paper.

A Simplified Model of a Surge Arrester and Its Application in Residual Voltage Tests

A simplified and accurate model of a surge arrester used in the residual voltage test is proposed in this paper. With the help of a genetic algorithm, the measured impulse current and residual voltage waveforms are utilized to determine circuit parameters of the proposed model and the generation circuit precisely. The technique starts from the circuit parameter determination using the preliminary experimental data with a lower current peak than that specified by the standard. From the determined model and with the help of the genetic algorithm, the circuit parameters and the charging voltage to obtain the specified current peak and the residual voltage can be estimated accurately. The validity of the proposed technique has been verified by experiments for the estimation of the appropriate current circuit parameters, the charging voltage, and the residual voltage. In addition, the application of the proposed model in the residual voltage tests is presented. From comparison of simulated and experimental results with the determined parameters, the impulse current and residual voltage waveforms are determined precisely. It is confirmed that the proposed model and technique are attractive in the appropriate circuit parameter determination and the residual voltage estimation in the residual voltage tests of surge arresters. The proposed method also provides a good advantage for reduction of the number of trial and error experiments for obtaining the current waveform according to the standard requirement. Moreover, the unintentional damages of the arrester during the process of the waveform adjustment will be reduced significantly.

IMAGE-FORMING BY MEANS OF AXICON

A theoretical analysis of the image-forming properties of the conical axicon in the scalar diffraction Kirchhoff-Fresnel approximation within the framework of the theory of linear systems revealed that the classical concept of the point spread function is not applicable to axicon images. In the near diffraction zone, a point light source is imaging by a conical axicon in the form of a segment along a straight line connecting the source and the center of the axicon. Moreover, different annular areas of the axicon form different sections on this segment. When used in tandem with a lens, the axicon can allow to increase the depth of focus. Preliminary experimental data have been obtained, which confirm the theoretical conclusions.

METHODS OF THE ESTIMATED TWO-PARAMETER LINEAR REGRESSION MODELSFOR DIAGNOSIS OF BRONCHIAL ASTHMA SEVERITY IN CHILDREN

Objectives: Prognostication of bronchial asthma severity in children by means of two-parameter regression models building. Methods: A clinical study of 70 children with bronchial asthma diagnosis of 6 to 18 years old was done.142 factors were analyzed and a degree of relationship among them was revealed. Single-factor regression models were used during preliminary experimental data processing. Results: The correlation connection between the value observed and the factors under research was revealed. The method of two-parameter linear models with a fair accuracy was developed. Conclusion: The suggested method of approximate two-parameter linear regression models can be used for preliminary analysis of medical research data where the value observed depends on a big number of loosely connected factors.

Traces of Wood and Bone Processing on the Volcanic Flint of the Dunda- Aga Paleovolcano: The Preliminary Experimental Data

The article is a description of an experiment on planing the raw and dry wood, as well as boiled bone, which was carried out by flakes from volcanic flint from the raw material source of the Dunda-Aga paleovolcano, located in the Aginsky Buryat district of the Transbaikal region. In its course, changes in the working edge of the tools were monitored using binocular and metallographic microscopes, as well as photographic recording of these results using digital cameras and Helicon Focus v. 5.3. During the experiment, it was possible to identify a tendency for the formation of macro and micro wear of the surface of the working edge of objects, depending on the material processed by planing. It was found that on volcanic flint, in places of the most intense contact with a hard surface to be treated, micropolishing in individual microsections is formed already within the first 30 minutes of operation. Then these areas expand and close along the length of the working edge. Over time, tools that work dry wood show a fine micro-polish line, while wet wood forms a more discontinuous line of different widths. Bone processing showed the strongest modification of the tool. After an hour of work, it became dull due to intense rounding, and after two hours it almost completely lost its effectiveness. The results of this experiment clarify the dynamics of the formation of macro and micro wear on tools made of volcanic flint when processing dry and damp wood, as well as bone. Keywords: microwear analysis, petroarcheology, the sources of raw materials, Stone Age, Transbaikalia, Dunda-Aga paleovolcano, volcanic flint Acknowledgements: The work was supported by a grant from the Transbaikal State University No. 292‑ГР.

A possible role for epigenetic feedback regulation in the dynamics of the Epithelial-Mesenchymal Transition (EMT)

The epithelial-mesenchymal transition (EMT) often plays a critical role in cancer metastasis and chemoresistance, and decoding its dynamics is crucial to design effective therapeutics. EMT is regulated at multiple levels transcriptional, translational, protein stability, and epigenetics; the mechanisms by which epigenetic regulation can alter the dynamics of EMT remain elusive. Here, to identify the possible effects of epigenetic regulation in EMT, we incorporate a feedback term in our previously proposed model of EMT regulation of the miR 200/ZEB/miR 34/SNAIL circuit. This epigenetic feedback that stabilizes long-term transcriptional activity can alter the relative stability and distribution of states in a given cell population, particularly when incorporated in the inhibitory effect on miR 200 from ZEB. This feedback can stabilize the mesenchymal state, thus making transitions out of that state difficult. Conversely, epigenetic regulation of the self activation of ZEB has only minor effects. Our model predicts that this effect could be seen in experiments, when epithelial cells are treated with an external EMT inducing signal for a sufficiently long period of time and then allowed to recover. Our preliminary experimental data indeed shows that a prolonged TGF beta; exposure gives rise to increasing difficult reversion back to the epithelial state. Thus, this integrated theoretical experimental approach yields insights into how an epigenetic feedback may alter the dynamics of EMT.

Mechanistic Models of Inducible Synthetic Circuits for Joint Description of DNA Copy Number, Regulatory Protein Level, and Cell Load

Accurate predictive mathematical models are urgently needed in synthetic biology to support the bottom-up design of complex biological systems, minimizing trial-and-error approaches. The majority of models used so far adopt empirical Hill functions to describe activation and repression in exogenously-controlled inducible promoter systems. However, such equations may be poorly predictive in practical situations that are typical in bottom-up design, including changes in promoter copy number, regulatory protein level, and cell load. In this work, we derived novel mechanistic steady-state models of the lux inducible system, used as case study, relying on different assumptions on regulatory protein (LuxR) and cognate promoter (Plux) concentrations, inducer-protein complex formation, and resource usage limitation. We demonstrated that a change in the considered model assumptions can significantly affect circuit output, and preliminary experimental data are in accordance with the simulated activation curves. We finally showed that the models are identifiable a priori (in the analytically tractable cases) and a posteriori, and we determined the specific experiments needed to parametrize them. Although a larger-scale experimental validation is required, in the future the reported models may support synthetic circuits output prediction in practical situations with unprecedented details.

Preliminary Studies of Synthetic Dye Adsorption on Iron Sludge and Activated Carbons

There is great interest in the search for multifunctional waste-based materials that may be applied as environmentally friendly adsorbents. Iron-rich sludge from ground drinking-water treatment plants may be considered a potential adsorbent for various water contaminants. This material is generated during ground water purification because of the excess of metal ions in water (Fe, Mn). In practice, this sludge is frequently disposed of as waste material and, so far, is not commonly applied as the adsorption base. Our research aims to explore the adsorption potential of iron sludge for selected synthetic dyes, including malachite green, ponceau 4R, and brilliant blue FCF. Experimental data were performed using iron sludge collected from the Groundwater Treatment Plant in Koszalin, Poland, and comparing it with adsorption properties of commercial activated carbons (Norit SA Super and Norit CA 1). The kinetics, adsorption isotherms, and temperature influence on the removal of target dyes were investigated and discussed. Preliminary experimental data have revealed that iron sludge can be considered an adsorbent for the removal of cationic dyes.