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21.
There is a huge interest in making and applying innovating functional devices based on basic sciences (like physics) to improve plant growth and resistance against various stress conditions. This research was carried out in order to investigate effects of cold plasma on expressions of heat shock factor A4A (HSFA4A), plant growth and post reactions to salt stress. Wheat seedlings were treated with plasma (0.84 W/cm2 surface power densities) at different exposure times. In both three and 6 h after plasma, inductions in expressions of HSFA4A were recorded in roots, compared to control. Six hours after treatments, plasma-induced the shoot expressions of HSFA4A in the treated seedlings, contrasted to 3 h. Plasma treatment caused not the only enhancement in shoot fresh and dry mass and total leaf area, but also alleviated adverse impacts of salinity. Destroying impacts of salinity on chlorophyll contents were mitigated by plasma. Peroxidase activity was decreased by 27% for salinity treatment alone over control, while it was increased by 15% for plasma and salinity-treated samples, compared to salinity control. The highest activities of phenylalanine ammonia lyase (PAL) were found in plasma treatment alone. PAL activity was found to be higher in plasma-pretreated seedlings counteracted to salt stress, relative to the salinity control. The plasma treatment may act as an effective elicitor to modify gene expression, thereby improving plant growth and resistance. Plasma technology should be considered as a new functional technology in plant sciences.  相似文献   
22.
Ion exchange chromatography is widely used for charge variant analysis of proteins, including monoclonal antibodies. In this study, a simple and robust salt gradient cation exchange chromatography was developed and validated for quantitative determination of cetuximab in biopharmaceutical formulations. For this purpose, we investigated the effect of various parameters including buffer composition, column temperature, pH, gradient volume and flow rate on chromatographic separation of charge variants to achieve the acceptable peak separation, and the optimum condition was selected. Validation of the method was done in accordance with the International Conference on Harmonization (ICH) guidelines. The developed method was found to provide a linear regression over the concentration range of 0.06–2.00 mg mL?1 yielding a correlation coefficient of 0.9972. The limits of detection and quantification for the developed method were 0.02 and 0.06 mg mL?1, respectively. The intra-day and inter-day precision had relative standard deviation values?≤?2.7%. The robustness of the method was assessed by changes in the applied pH range of buffer, temperature, mobile phase composition, and flow rate. Specificity of the method was confirmed by evaluation of baseline resolution of the mAb variants from product excipients, which showed no interference between excipients and cetuximab. The stability indicating capability of this method was determined using photodegraded, and mechanically and thermally stressed samples. The proposed method could be applied as a simple, precise, and robust quantitative technique which can be reproduced in any labs for the high-throughput quality control and stability assessment of in-process and final product samples.  相似文献   
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24.
This paper proposes a new combustion model for the simulation of biomass combustion. It is developed based on the framework of the well-known Eddy Dissipation Concept (EDC) approach, which has the ability to incorporate chemical kinetics in turbulent reacting flows and thus makes it suitable for modelling gas-phase combustion. However, its high computational cost when using detailed chemistry has made it impractical for modelling large/industrial setups. To address this handicap, the proposed approach decouples the real-time calculation of chemical and mixing processes by importing a pre-calculated steady laminar flamelet library into EDC. The development of this new model is performed based on a modified version of EDC (called Extended EDC), which is capable of modelling the gas-phase of biomass combustion over a wide range of turbulent flow conditions. The proposed model is validated by simulating the well-documented experiment of the piloted jet flames of Barlow and Frank. The performance of the model is then evaluated by simulating a small-scale grate firing biomass furnace. The results show that, overall, the proposed model can be used to model biomass combustion at substantially low computational cost.  相似文献   
25.
Nonlinear Dynamics - In this paper, we analytically and numerically investigate chaos in attitude dynamics of a flexible satellite composed of a rigid body and two identical rigid panels attached...  相似文献   
26.
A method has been introduced for quantitative determination of protein content in yogurt samples based on the characteristic absorbance of protein in 1800-1500 cm− 1 spectral region by mid-FTIR spectroscopy and chemometrics. Successive Projection Algorithm (SPA) wavelength selection procedure, coupled with feed forward Back-Propagation Artificial Neural Network (BP-ANN) model was the benefited chemometric technique. Relative Error of Prediction (REP) in BP-ANN and SPA-BP-ANN methods for training set was 7.25 and 3.70 respectively. Considering the complexity of the sample, the ANN model was found to be reliable, while the proposed method is rapid and simple, without any sample preparation step.  相似文献   
27.
Based on the theory of stabilization of fractional-order LTI interval systems, a simple controller for stabilization of a class of fractional-order chaotic systems is proposed in this paper. We consider the structure of the chaotic systems as fractional-order LTI interval systems due to the limited amplitude of chaotic trajectories. We introduce a simple feedback controller for the interval system and then, based on a recently established theorem for stabilization of interval systems, we reach to a linear matrix inequality (LMI) problem. Solving the LMI yields an appropriate decoupling feedback control law which suffices to bring the chaotic trajectories to the origin. Several illustrative examples are given which show the effectiveness of the method.  相似文献   
28.
In the multi-component configurations of dark matter phenomenology,we propose a minimal twocomponent configuration which is an extension of the Standard Model with only three new fields;one scalar and one fermion interact with the thermal soup through Higgs portal,mediated by the other scalar in such a way that the stabilities of dark matter candidates are made simultaneously by an explicit Z2 symmetry.Against the most common freeze-out framework,we look for dark matter particle signatures in the freeze-in scenario by evaluating the relic density and detection signals.A simple distinguishing feature of the model is the lack of dark matter conversion,so the dark matter components act individually and the model can be adapted entirely to both singlet scalar and singlet fermionic models,separately.We find dark matter self-interaction as the most promising approach to probe such feeble models.Although the scalar component satisfies this constraint,the fermionic one refuses it even in the resonant region.  相似文献   
29.
The morphology, thermal degradation behavior in addition to static and dynamic mechanical properties of various ethylene?Cpropylene?Cdiene (EPDM) rubber compounds containing nano-zinc oxide (NZnO) were investigated compared to those of EPDM with ordinary-sized ZnO (OSZnO). The field-emission scanning electron microscopy studies showed that unlike the conventional system, the formation of large size ZnO agglomerates was discouraged for NZnO filled systems. Thermogravimetric analysis (TG) revealed that the thermal degradation of EPDM system was delayed upon the inclusion of NZnO instead of OSZnO in the compound. The kinetic analysis of TG data based on Friedman and Kissinger methods showed that the nanocomposite samples exhibited higher activation energy (E a ) and lower order of reaction (n) over the conventional system, suggesting the enhancement of thermal stability upon decreasing ZnO particle size. The results obtained from dynamic mechanical analysis and static mechanical characterizations in terms of hardness, resilience, and abrasion tests interestingly indicated that NZnO not merely could act as a thermal insulator, but also could perform as a nano-filler to improve the final performance of EPDM elastomers.  相似文献   
30.
Cyanide is a poisonous and dangerous chemical that binds to metals in metalloenzymes, especially cytochrome C oxidase and, thus, interferes with their functionalities. Different pathways and enzymes are involved during cyanide biodegradation, and cyanide hydratase is one of the enzymes that is involved in such a process. In this study, cyanide resistance and cyanide degradation were studied using 24 fungal strains in order to find the strain with the best capacity for cyanide bioremediation. To confirm the capacity of the tested strains, cyano-bioremediation and the presence of the gene that is responsible for the cyanide detoxification was assessed. From the tested organisms, Trichoderma harzianum (T. harzianum) had a significant capability to resist and degrade cyanide at a 15 mM concentration, where it achieved an efficiency of 75% in 7 days. The gene network analysis of enzymes that are involved in cyanide degradation revealed the involvement of cyanide hydratase, dipeptidase, carbon–nitrogen hydrolase-like protein, and ATP adenylyltransferase. This study revealed that T. harzianum was more efficient in degrading cyanide than the other tested fungal organisms, and molecular analysis confirmed the experimental observations.  相似文献   
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