Journal articles: 'Modulating functions method'

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Stark, Oliver, Marius Eckert, Albertus Johannes Malan, and Sören Hohmann. "Fractional Systems’ Identification Based on Implicit Modulating Functions." Mathematics 10, no. 21 (November 3, 2022): 4106. http://dx.doi.org/10.3390/math10214106.

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This paper presents a new method for parameter identification based on the modulating function method for commensurable fractional-order models. The novelty of the method lies in the automatic determination of a specific modulating function by controlling a model-based auxiliary system, instead of applying and parameterizing a generic modulating function. The input signal of the model-based auxiliary system used to determine the modulating function is designed such that a separate identification of each individual parameter of the fractional-order model is enabled. This eliminates the shortcomings of the common modulating function method in which a modulating function must be adapted to the investigated system heuristically.

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Liu, Da-Yan, and Taous-Meriem Laleg-Kirati. "Robust fractional order differentiators using generalized modulating functions method." Signal Processing 107 (February 2015): 395–406. http://dx.doi.org/10.1016/j.sigpro.2014.05.016.

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Tarasenko, Anna. "Method of SAR sounding signals investigation and digital forming." ITM Web of Conferences 30 (2019): 15030. http://dx.doi.org/10.1051/itmconf/20193015030.

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Fedele, Giuseppe, and Loredana Coluccio. "A recursive scheme for frequency estimation using the modulating functions method." Applied Mathematics and Computation 216, no. 5 (May 2010): 1393–400. http://dx.doi.org/10.1016/j.amc.2010.02.039.

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Pumaricra Rojas, David, Matti Noack, Johann Reger, and Gustavo Pérez-Zúñiga. "State Estimation for Coupled Reaction-Diffusion PDE Systems Using Modulating Functions." Sensors 22, no. 13 (July 2, 2022): 5008. http://dx.doi.org/10.3390/s22135008.

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Many systems with distributed dynamics are described by partial differential equations (PDEs). Coupled reaction-diffusion equations are a particular type of these systems. The measurement of the state over the entire spatial domain is usually required for their control. However, it is often impossible to obtain full state information with physical sensors only. For this problem, observers are developed to estimate the state based on boundary measurements. The method presented applies the so-called modulating function method, relying on an orthonormal function basis representation. Auxiliary systems are generated from the original system by applying modulating functions and formulating annihilation conditions. It is extended by a decoupling matrix step. The calculated kernels are utilized for modulating the input and output signals over a receding time window to obtain the coefficients for the basis expansion for the desired state estimation. The developed algorithm and its real-time functionality are verified via simulation of an example system related to the dynamics of chemical tubular reactors and compared to the conventional backstepping observer. The method achieves a successful state reconstruction of the system while mitigating white noise induced by the sensor. Ultimately, the modulating function approach represents a solution for the distributed state estimation problem without solving a PDE online.

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Preisig, H. A., and D. W. T. Rippin. "Theory and application of the modulating function method—II. algebraic representation of Maletinsky's spline-type modulating functions." Computers & Chemical Engineering 17, no. 1 (January 1993): 17–28. http://dx.doi.org/10.1016/0098-1354(93)80002-5.

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He, Shanghong. "PARAMETER ESTIMATION OF LINEAR CONTINUOUS-TIME DYNAMIC SYSTEM USING MODULATING FUNCTIONS METHOD." Chinese Journal of Mechanical Engineering 39, no. 12 (2003): 129. http://dx.doi.org/10.3901/jme.2003.12.129.

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Fedele, G., C. Picardi, and D. Sgro. "A Power Electrical Signal Tracking Strategy Based on the Modulating Functions Method." IEEE Transactions on Industrial Electronics 56, no. 10 (October 2009): 4079–87. http://dx.doi.org/10.1109/tie.2009.2028352.

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Preisig, H. A., and D. W. T. Rippin. "Theory and application of the modulating function method—I. Review and theory of the method and theory of the spline-type modulating functions." Computers & Chemical Engineering 17, no. 1 (January 1993): 1–16. http://dx.doi.org/10.1016/0098-1354(93)80001-4.

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Co, Tomas B., and Sridhar Ungarala. "Batch scheme recursive parameter estimation of continuous-time systems using the modulating functions method." Automatica 33, no. 6 (June 1997): 1185–91. http://dx.doi.org/10.1016/s0005-1098(97)00020-4.

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Byrski, Witold, Michał Drapała, and Jȩdrzej Byrski. "An Adaptive Identification Method Based on the Modulating Functions Technique and Exact State Observers for Modeling and Simulation of a Nonlinear Miso Glass Melting Process." International Journal of Applied Mathematics and Computer Science 29, no. 4 (December 1, 2019): 739–57. http://dx.doi.org/10.2478/amcs-2019-0055.

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Abstract The paper presents new concepts of the identification method based on modulating functions and exact state observers with its application for identification of a real continuous-time industrial process. The method enables transformation of a system of differential equations into an algebraic one with the same parameters. Then, these parameters can be estimated using the least-squares approach. The main problem is the nonlinearity of the MISO process and its noticeable transport delays. It requires specific modifications to be introduced into the basic identification algorithm. The main goal of the method is to obtain on-line a temporary linear model of the process around the selected operating point, because fast methods for tuning PID controller parameters for such a model are well known. Hence, a special adaptive identification approach with a moving window is proposed, which involves using on-line registered input and output process data. An optimal identification method for a MISO model assuming decomposition to many inner SISO systems is presented. Additionally, a special version of the modulating functions method, in which both model parameters and unknown delays are identified, is tested on real data sets collected from a glass melting installation.

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Asiri, Sharefa, and Taous-Meriem Laleg-Kirati. "Modulating functions-based method for parameters and source estimation in one-dimensional partial differential equations." Inverse Problems in Science and Engineering 25, no. 8 (October 20, 2016): 1191–215. http://dx.doi.org/10.1080/17415977.2016.1240793.

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Tian, Yang, Yan-Qiao Wei, Da-Yan Liu, and Driss Boutat. "Fast and robust estimation for positions and velocities from noisy accelerations using generalized modulating functions method." Mechanical Systems and Signal Processing 133 (November 2019): 106270. http://dx.doi.org/10.1016/j.ymssp.2019.106270.

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Daniel-Berhe, S., and H. Unbehauen. "Physical parameters estimation of the nonlinear continuous-time dynamics of a DC motor using Hartley modulating functions method." Journal of the Franklin Institute 336, no. 3 (April 1999): 481–501. http://dx.doi.org/10.1016/s0016-0032(98)00043-x.

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Lundberg, Karl-Ola. "An Alternative Method for Measurement of Airborne Sound Insulation." Building Acoustics 8, no. 1 (March 2001): 57–74. http://dx.doi.org/10.1260/1351010011501731.

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A method for determination of the transmission coefficient from Complex Modulation Transfer Functions CMTF:s based on measured impulse-responses is shown. In the method a separate measurement of the equivalent sound absorption area is not needed in contrast to in the standardised measurement. By averaging over a number of estimates of the impulse-response the influence of background noise can be reduced substantially, implying that low-power sources can be used. A model for the power balance in the receiving room with time-varying power is considered. In the model the quotient of the receiving room intensity and the source room intensity has one pole, which is proportional to the equivalent sound absorption area in the receiving room, and a gain, proportional to the transmission coefficient. In the physical system the power can be time-varied by letting the system excitation signal consist of random noise modulated with a deterministic time-varying function. However, since the ensemble average of the squared response is proportional to the squared impulse-response convolved with the squared modulating function, random excitation is avoided and replaced by impulse-response measurements. The quotient of intensities in the model is in the physical system a quotient of CMTF:s. Experiments are carried out in an airborne sound insulation laboratory. For comparison, standardised measurements are also carried out. It is found that the presented method gives as result comparatively small transmission coefficients, though the relative differences are small. By refining the power balance model by introducing an energy propagation time delay, and selecting an appropriate delay, the differences were diminished.

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Zhou, Guang-Dong, You-Liang Ding, and Ai-Qun Li. "Wavelet-Based Methodology for Evolutionary Spectra Estimation of Nonstationary Typhoon Processes." Mathematical Problems in Engineering 2015 (2015): 1–10. http://dx.doi.org/10.1155/2015/870420.

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Closed-form expressions are proposed to estimate the evolutionary power spectral density (EPSD) of nonstationary typhoon processes by employing the wavelet transform. Relying on the definition of the EPSD and the concept of the wavelet transform, wavelet coefficients of a nonstationary typhoon process at a certain time instant are interpreted as the Fourier transform of a new nonstationary oscillatory process, whose modulating function is equal to the modulating function of the nonstationary typhoon process multiplied by the wavelet function in time domain. Then, the EPSD of nonstationary typhoon processes is deduced in a closed form and is formulated as a weighted sum of the squared moduli of time-dependent wavelet functions. The weighted coefficients are frequency-dependent functions defined by the wavelet coefficients of the nonstationary typhoon process and the overlapping area of two shifted wavelets. Compared with the EPSD, defined by a sum of the squared moduli of the wavelets in frequency domain in literature, this paper provides an EPSD estimation method in time domain. The theoretical results are verified by uniformly modulated nonstationary typhoon processes and non-uniformly modulated nonstationary typhoon processes.

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Byrski, Witold, and Jęedrzej Byrski. "The role of parameter constraints in EE and OE methods for optimal identification of continuous LTI models." International Journal of Applied Mathematics and Computer Science 22, no. 2 (June 1, 2012): 379–88. http://dx.doi.org/10.2478/v10006-012-0028-3.

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The role of parameter constraints in EE and OE methods for optimal identification of continuous LTI modelsThe paper presents two methods used for the identification of Continuous-time Linear Time Invariant (CLTI) systems. In both methods the idea of using modulating functions and a convolution filter is exploited. It enables the proper transformation of a differential equation to an algebraic equation with the same parameters. Possible different normalizations of the model are strictly connected with different parameter constraints which have to be assumed for the nontrivial solution of the optimal identification problem. Different parameter constraints result in different quality of identification. A thorough discussion on the role of parameter constraints in the optimality of system identification is included. For time continuous systems, the Equation Error Method (EEM) is compared with the continuous version of the Output Error Method (OEM), which appears as a special sub-case of the EEM.

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Asiri, Sharefa, and Taous-Meriem Laleg-Kirati. "Source Estimation for the Damped Wave Equation Using Modulating Functions Method: Application to the Estimation of the Cerebral Blood Flow." IFAC-PapersOnLine 50, no. 1 (July 2017): 7082–88. http://dx.doi.org/10.1016/j.ifacol.2017.08.1356.

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Laplante, Véronique, Ulysse Nadeau, Marine Rousseau, Sylvie Lesage, Jean-François Gauchat, and Sarah Pasquin. "Detection of Cardiotrophin-like Cytokine Factor 1 (CLCF1) by flow cytometry." Journal of Immunology 206, no. 1_Supplement (May 1, 2021): 22.12. http://dx.doi.org/10.4049/jimmunol.206.supp.22.12.

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Abstract Cardiotrophin-like Cytokine Factor 1 (CLCF1) belongs to the IL6 family of cytokines and possesses pro-neurotrophic and immuno-modulating functions. Coding mRNA for CLCF1 has been detected in primary and secondary lymphoid organs (i.e. lymph nodes, spleen and bone marrow), as well as in the lungs and feminine reproductive organs. Modulation of CLCF1’s mRNA levels has been associated with the Th17 polarization in CD4+ T cells. However, little information is available regarding CLCF1 protein levels in these tissues or the nature of the immune cells responsible for its production. This can be explained by a lack of in situ detection options for CLCF1. We have therefore developed a methodology for the detection of human and murine CLCF1 by flow cytometry in permeabilized cells. This technique has been validated using derivatives of the Ba/F3 cell line in which cDNAs coding for human and murine CLCF1 were introduced by transduction with recombinant retroviruses. We are currently using this approach to study CLCF1 production by human and murine immune cells. Preliminary results indicate a production of CLCF1 by Th17 T cells. The development of a method to detect CLCF1 by flow cytometry will be beneficial for the study of CLCF1’s functions in the regulation of the immune response.

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Mykhailenko, Vladyslav, Vadym Svyatnenko, Yuliya Chunyak, and Vladyslav Bachynskiy. "Research of processes in a converter with four-zone voltage regulation and electromechanical load." Bulletin of NTU "KhPI". Series: Problems of Electrical Machines and Apparatus Perfection. The Theory and Practice, no. 1 (5) (May 28, 2021): 39–41. http://dx.doi.org/10.20998/2079-3944.2021.1.07.

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The new mathematical models of the electromagnetic processes is designed in three-phase electric circuit of the semiconductor converters with many-server zoned regulation phases voltages disregarding losses in semiconductor commutator for quick estimation of the influence parameter loads on level and form of the output voltage. mathematical model of the semiconductor converter is also used for study of the connecting processes in semiconductor converter with actively-inductive load. Will develop the method multivariable function, what fall into algorithmic equations of the analysis formed and connecting processes in furcated electric circuit with semiconductor commutator and reactive element, toward account of the particularities of the use phase and linear voltages to network of the power supply. Analysis of the electromagnetic processes is organized beside this article in electric circuit with semiconductor commutator. Mathematical model is created for analysis electro-magnetic processes in semiconductor converter with width pulsed regulation of the output voltage. The broughted graphs, which reflect the electromagnetic processes in electric circuit. Method much parametric functions was used when performing calculation. The mathematical model of the converter is created for eleven zoned regulations of the output voltage. Article is devoted to the development of a method of multi-parametric modulating functions by means of working out of new mathematical models and definition of functions and the algorithmic equations for the analysis on sub-system components of electromagnetic processes in electric circuits of variable structure with sinusoidal, direct and pulsing voltage. Introduction of functions with discrete parameters in the algorithmic equations for analysis of processes in circuits with semiconductor commutators simplifies modeling on subsystem components. The mathematical model of steady-state processes and transients in electric circuits of semiconductor converters of modulation type with multi-channel zonal use of phase and line voltages of a three-phase network of power supplies is developed. The mathematical model of electric circuits of thyristor shapers of electro-discharge pulses for the analysis and the matching of capacitors charging modes with decrease several times of electric resistance of technological load is also created.

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21

Ishihara, Seiichiro, Haruna Kurosawa, and Hisashi Haga. "Stiffness-Modulation of Collagen Gels by Genipin-Crosslinking for Cell Culture." Gels 9, no. 2 (February 10, 2023): 148. http://dx.doi.org/10.3390/gels9020148.

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The stiffness of extracellular matrices (ECMs) is critical for cellular functions. Therefore, modulating the stiffness of ECMs in vitro is necessary to investigate the role of stiffness in cellular phenomena. Collagen gels are widely used for cell culture matrices in vitro. However, modulation of the stiffness in collagen gels for cell culture is challenging owing to the limited knowledge of the method to increase the stiffness while maintaining low cytotoxicity. Here, we established a novel method to modulate collagen gel stiffness from 0.0292 to 12.5 kPa with low cytotoxicity. We prepared collagens with genipin, a low-cytotoxic crosslinker of amines, at different concentrations and successfully modulated the stiffness of the gels. In addition, on 10 mM genipin-mixed collagen gels (approximately 12.5 kPa), H1299 human lung cancer cells showed spreading morphology and nuclear localization of yes-associated protein (YAP), typical phenomena of cells on stiff ECMs. Mouse mesenchymal stromal cells on 10 mM genipin-mixed collagen gels differentiated to vascular smooth muscle cells. On the other hand, the cells on 0 mM genipin-mixed collagen gels (approximately 0.0292 kPa) differentiated to visceral smooth muscle cells. Our new method provides a novel way to prepare stiffness-modulated collagen gels with low cytotoxicity in cell culture.

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Gyurova, Ivayla E., Hannah Than Win, and Stephen N. Waggoner. "Non-canonical functions of adaptive natural killer cells." Journal of Immunology 204, no. 1_Supplement (May 1, 2020): 154.7. http://dx.doi.org/10.4049/jimmunol.204.supp.154.7.

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Abstract Natural killer (NK) cells are critical for the control of cytomegalovirus (CMV) infections in both mice and humans. Subsets of phenotypically and functionally distinct adaptive NK cells accumulate after CMV infection and potentially represent desirable new targets for a preventive CMV vaccine owing to their putatively greater antiviral functionality. However, our lab and others have described a series of non-canonical functions of NK cells that prevent harmful disease outcomes by modulating the responses of other leukocytes. In fact, we now demonstrate that bulk human blood NK cells can suppress CMV-specific T cell responses during in vitro culture. We reason that amplification of these non-canonical functions within an expanded subset of virus-induced adaptive NK cells would be beneficial to health in the context of virus persistence. In order to compare the canonical antiviral and non-canonical immunoregulatory functions of conventional and adaptive NK cells, we first sought to determine if it was possible to expand these subsets using K562 feeder cells with membrane bound IL-21. Similar to our recent longitudinal clinical profiling of adaptive NK cells (Gyurova et al. 2019), we observed variable increase or decrease in the baseline frequencies of adaptive (i.e. FcRγneg) NK cells following ex vivo expansion of cells from disparate healthy donors. Ex vivo expanded NK subsets demonstrated a reduced capacity to kill K562 cells. These results establish a method for obtaining sufficient quantities of adaptive and conventional NK cells for functional evaluation of antiviral and regulatory activity.

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Cardarelli, Mariateresa, Youssef Rouphael, Marios C. Kyriacou, Giuseppe Colla, and Catello Pane. "Augmenting the Sustainability of Vegetable Cropping Systems by Configuring Rootstock-Dependent Rhizomicrobiomes that Support Plant Protection." Agronomy 10, no. 8 (August 13, 2020): 1185. http://dx.doi.org/10.3390/agronomy10081185.

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Herbaceous grafting is a propagation method largely used in solanaceous and cucurbit crops for enhancing their agronomic performances especially under (a)biotic stress conditions. Besides these grafting-mediated benefits, recent advances about microbial networking in the soil/root interface, indicated further grafting potentialities to act as soil environment conditioner by modulating microbial communities in the rhizosphere. By selecting a suitable rootstock, grafting can modify the way of interacting root system with the soil environment regulating the plant ecological functions able to moderate soilborne pathogen populations and to decrease the risk of diseases. Genetic resistance(s) to soilborne pathogen(s), root-mediate recruiting of microbial antagonists and exudation of antifungal molecules in the rhizosphere are some defense mechanisms that grafted plants may upgrade, making the cultivation less prone to the use of synthetic fungicides and therefore more sustainable. In the current review, new perspectives offered by the available literature concerning the potential benefits of grafting, in enhancing soilborne disease resistance through modulation of indigenous suppressive microbial communities are presented and discussed.

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Deng, Meihong, Li Xu, Rosemary Hoffmann, and Timothy R. Billiar. "TLR9 regulates host defense via modulation of peritoneal B1 cell recruitment and functions during intra-abdominal sepsis." Journal of Immunology 200, no. 1_Supplement (May 1, 2018): 114.8. http://dx.doi.org/10.4049/jimmunol.200.supp.114.8.

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Abstract Background Toll like receptor 9 (TLR9) is identified as anintracellular DNA receptor playing important roles in immunity. However, the mechanisms of how TLR9 regulates host defense are unclear. B1 cells are aninnate-like B cell population predominately residing in peritoneum and highly express TLR9. Therefore, we hypothesize that TLR9 may regulate host defense via modulation of peritoneal B1 pathobiology during sepsis. Method C57BL/6 (WT) mice and TLR9−/− mice were subjected to cecal ligation and puncture (CLP) with for 18 hours. Result Deletion of TLR9 increased survival as well as decreased bacterial load and systemic inflammation after CLP. Interestingly, peritoneal B1 cell numbers were significantly higher in TLR9−/− than WT mice, associated with significant increases of peritoneal CXCL13 level in TLR9−/− miceat baseline and after CLP. Strikingly, the expression level of CXCL13, a B cell-attracting chemokine, in the mesenteric adipo tissue was 50 fold higher inTLR9−/− than WT mice after CLP. Treatment with CXCL13 neutralizing antibody impaired bacterial clearance and decreased peritoneal B1 cell numbersin TLR9−/− mice compared to the IgG control after CLP, suggesting that TLR9 regulated B1 cell recruitment via CXCL13. Furthermore, deletion of TLR9 significantly increased peritoneal natural antibody IgM levels compared to WT at baseline and after CLP. Importantly, adoptive transfer of TLR9−/−B1 cells to WT mice improved bacterial clearance and increased peritoneal IgM levels compared to adoptive transfer of WT B1 cells after CLP. Conclusions These findings revealed an unrecognized role of TLR9 in modulating host defense via regulating B1 cell recruitment and IgM production during intra-abdominal sepsis.

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Tian, Ling, Rongsheng E. Wang, Ying Fei, and Yie-Hwa Chang. "A Homogeneous Fluorescent Assay for cAMP-Phosphodiesterase Enzyme Activity." Journal of Biomolecular Screening 17, no. 3 (November 7, 2011): 409–14. http://dx.doi.org/10.1177/1087057111426901.

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Cyclic adenosine monophosphate–phosphodiesterases (cAMP-PDEs) regulate the cellular level of cAMP by selectively catalyzing the hydrolysis of the phosphodiester bond in the cAMP molecule. They play important roles in modulating cellular and physiological functions. There is a growing interest in the study of cAMP-PDEs as therapeutic targets. We describe a novel method for measuring the enzyme activity of cAMP-PDEs that is based on a homogeneous fluorescence assay employing a cAMP-dependent DNA-binding protein (CAP). We demonstrate that the assay is quick and robust compared to traditional methods and is expected to be cost-effective for high-throughput screening of cAMP-PDE inhibitors. The usefulness of the assay is demonstrated by measuring IC50 values of three nonselective PDE inhibitors and by kinetic measurements of cAMP-PDEs from various rat tissues.

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Mihaylenko, V., J. Chunyak, and V. Bachinskiy. "Analysis of processes in converter with eleven zone regulation output voltage." POWER ENGINEERING: economics, technique, ecology, no. 3 (April 6, 2020): 35–40. http://dx.doi.org/10.20535/1813-5420.3.2020.228610.

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Analysis of the electromagnetic processes is organized beside this article in electric circuit with semiconductor commutator . Mathematical model is created for analysis electro-magnetic processes in semiconductor converter with width pulsed regulation of the output voltage. The broughted graphs, which reflect the electromagnetic processes in electric circuit. Method much parametric functions was used when performing calculation. The mathematical model of the converter is created for eleven zoned regulations of the output voltage. Article is devoted to the development of a method of multi-parametric modulating functions by means of working out of new mathematical models and definition of functions and the algorithmic equations for the analysis on sub- system components of electromagnetic processes in electric circuits of variable structure with sinusoidal, direct and pulsing voltage. Introduction of functions with discrete parameters in the algorithmic equations for analysis of processes in circuits with semiconductor commutators simplifies modeling on subsystem components. The mathematical model of steady-state processes and transients in electric circuits of semiconductor converters of modulation type with multi-channel zonal use of phase and line voltages of a three-phase network of power supplies is developed. The mathematical model of electric circuits of thyristor shapers of electro-discharge pulses for the analysis and the matching of capacitors charging modes with decrease several times of electric resistance of technological load is also created. The obtained results have a great value for development theoretical electrical engineering in a direction of simplification of calculations of electromagnetic processes in electric circuits with semi-conductor converters of the electric power. The Electromagnetic processes in electric circuit under width- pulse regulation possible to analyse with use the algorithmic equations multivariable function, which argument are a system parameters semiconductor commutator, signal of control, phases to network of the power supply and time. Introduction multivariable function with discrete parameter in algorithmic equations of the analysis formed and connecting processes in electric circuit of the variable structure allows to reflect change of this structure under system components, simplifying modeling and analysis of such processes to account of the generalization of the got equations. Except specified correlations and diagrams designed model allows to analyse forms of the output voltages and current of the separate power modules.

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Xia, Shaofeng, and Chenliang Wang. "Hsa_circ_0003220 Drives Chemoresistance of Human NSCLC Cells by Modulating miR-489-3p/IGF1." International Journal of Genomics 2023 (June 16, 2023): 1–12. http://dx.doi.org/10.1155/2023/8845152.

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Circular RNAs (circRNAs) have been shown to have critical roles in developing cancer and treatment resistance in an increasing body of research. The aim was to look into the functions and processes of hsa_circ_0003220 in the non-small cell lung cancer (NSCLC) chemoresistance. The NSCLC cell lines H460 and A549 were employed in present work. hsa_circ_0003220, miR-489-3p, and insulin-like growth factors (IGF1) mRNA levels were assessed with a quantitative real time polymerase chain reaction (qRT-PCR). The cisplatin, docetaxel, and paclitaxel (PTX) resistances were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, and the enzyme linked immunosorbent assay (ELISA) test measured IGF1 expression. In order to corroborate the miR-489-3p relation with hsa_circ_0003220 or IGF1, a dual-luciferase reporter method was applied. The level of hsa_circ_0003220 was raised in cells and tissues from PTX-resistant (PR) NSCLC. In PR NSCLC cells, hsa_circ_0003220 knockdown reduced chemoresistance. For the purpose of the mechanism study, hsa_circ_0003220 knockdown substantially reduced IGF1 expression via miR-489-3p sponging, reducing chemoresistance in PR NSCLC cells. By controlling the miR-489-3p/IGF1 axis, hsa_circ_0003220 knockdown helped NSCLC overcome chemoresistance, suggesting a potential circRNA-targeted therapy for the disease.

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Popova, TA, II Prokofiev, IS Mokrousov, Valentina Perfilova, AV Borisov, SA Lebedeva, GP Dudchenko, IN Tyurenkov, and OV Ostrovsky. "Effects of Neuroactive Amino Acids Derivatives on Cardiac and Cerebral Mitochondria and Endothelial functions in Animals Exposed to Stress." Journal of Clinical and Health Sciences 2, no. 2 (December 31, 2017): 34. http://dx.doi.org/10.24191/jchs.v2i2.5885.

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Introduction: To study the effects of glufimet, a new derivative of glutamic acid, and phenibut, a derivative of γ-aminobutyric acid (GABA), on cardiac and cerebral mitochondria and endothelial functions in animals following exposure to stress and inducible nitric oxide synthase (iNOS) inhibition. Methods: Rats suspended by their dorsal cervical skin fold for 24 hours served as the immobilization and pain stress model. Arterial blood pressure was determined using a non-invasive blood pressure monitor. Mitochondrial fraction of heart and brain homogenates were isolated by differential centrifugation and analysed for mitochondrial respiration intensity, lipid peroxidation (LPO) and antioxidant enzyme activity using polarographic method. The concentrations of nitric oxide (NO) terminal metabolites were measured using Griess reagent. Hemostasis indices were evaluated. Platelet aggregation was estimated using modified version of the Born method described by Gabbasov et al., 1989. Results: The present study demonstrated that stress leads to an elevated concentration of NO terminal metabolites and LPO products, decreased activity of antioxidant enzymes, reduced mitochondrial respiratory function, and endothelial dysfunction. Inhibition of iNOS by aminoguanidine had a protective effect. Phenibut and glufimet inhibited a rise in stress-induced nitric oxide production. This resulted in enhanced coupling of substrate peroxidation and ATP synthesis. The reduced LPO processes caused by glufimet and phenibut normalized the endothelial function which was proved by the absence of average daily blood pressure (BP) elevation episodes and a significant increase in platelet aggregation level. Conclusion: Glufimet and phenibut restrict the harmful effects of stress on the heart and brain possibly by modulating iNOS activity.

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Tabansky, Inna, Yupu Liang, Maya Frankfurt, Martin A. Daniels, Matthew Harrigan, Sarah Stern, Teresa A. Milner, et al. "Molecular profiling of reticular gigantocellularis neurons indicates that eNOS modulates environmentally dependent levels of arousal." Proceedings of the National Academy of Sciences 115, no. 29 (July 2, 2018): E6900—E6909. http://dx.doi.org/10.1073/pnas.1806123115.

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Neurons of the medullary reticular nucleus gigantocellularis (NGC) and their targets have recently been a focus of research on mechanisms supporting generalized CNS arousal (GA) required for proper cognitive functions. Using the retro-TRAP method, we characterized transcripts enriched in NGC neurons which have projections to the thalamus. The unique expression and activation of the endothelial nitric oxide (eNOS) signaling pathway in these cells and their intimate connections with blood vessels indicate that these neurons exert direct neurovascular coupling. Production of nitric oxide (NO) within eNOS-positive NGC neurons increases after environmental perturbations, indicating a role for eNOS/NO in modulating environmentally appropriate levels of GA. Inhibition of NO production causes dysregulated behavioral arousal after exposure to environmental perturbation. Further, our findings suggest interpretations for associations between psychiatric disorders and mutations in the eNOS locus.

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Мihaylenko, V., J. Chunyak, K. Trubitsin, and V. Bachynskiy. "MATHEMATICAL MODEL OF A TWELVE-PULSE CONVERTER WITH SIXTEEN ZONE CONTROL OF THE OUTPUT VOLTAGE AND ACTIVE-INDUCTIVE LOADS." Collection of scholarly papers of Dniprovsk State Technical University (Technical Sciences) 2, no. 37 (April 23, 2021): 68–72. http://dx.doi.org/10.31319/2519-2884.37.2020.13.

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Analysis of the electromagnetic processes is organized in this article in electric circuit with semiconductor commutator. Mathematical model twelve pulses of the converter is created for analysis of the electromagnetic processes in semiconductor converter with width-pulse regulation of the output voltage. The broughted graphs, which reflect the electromagnetic processes in electric circuit. Method multivariable function was used when performing calculation. The mathematical model of the converter is created for five zoned regulations of the output voltage. Using method multivariable function was found current and voltage of the load, as well as input currents of the converter. The load of the converter has actively inductive nature. Article is devoted to the development of a method of multi-parametric modulating functions by means of working out of new mathematical models and definition of functions and the algorithmic equations for the analysis on sub-system components of electromagnetic processes in electric circuits of variable structure with sinusoidal, direct and pulsing voltage. Introduction of functions with discrete parameters in the algorithmic equations for analysis of processes in circuits with semiconductor commutators simplifies modeling on subsystem components. The mathematical model of steady-state processes and transients in electric circuits of semiconductor converters of modulation type with multi-channel zonal use of phase and line voltages of a three-phase network of power supplies is developed. The mathematical model of electric circuits of thyristor shapers of electro-discharge pulses for the analysis and the matching of capacitors charging modes with decrease several times of electric resistance of technological load is also created. The obtained results have a great value for development theoretical electrical engineering in a direction of simplification of calculations of electromagnetic processes in electric circuits with semi-conductor converters of the electric power. The electromagnetic processes in electric circuit under width-pulse regulation possible to analyse with use the algorithmic equations multivariable function, which argument are a system parameters semiconductor commutator, signal of control, phases to network of the power supply and time. Introduction multivariable function with discrete parameter in algorithmic equations of the analysis formed and connecting processes in electric circuit of the variable structure allows to reflect change of this structure under system components, simplifying modeling and analysis of such processes to account of the generalization of the got equations. Except specified correlations and diagrams designed model allows to analyse forms of the output voltages and current of the separate power modules.

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Matyash, I. Ye, I. A. Minailova, O. M. Mischuk, and B. K. Serdega. "Component Analysis of Radiation-Induced Thermoe-lasticity Using Modulation Polarimetry." Ukrainian Journal of Physics 63, no. 11 (December 1, 2018): 994. http://dx.doi.org/10.15407/ujpe63.11.994.

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A radiation field of an external or internal origin creates a non-uniform temperature gradient in a glass specimen. In this case, there appears a heat flux in the specimen, which generates mechanical stresses and induces an optical anisotropy in the form of birefringence. In this work, using the optical-polarization method, the birefringence magnitude is measured as the phase difference between the orthogonal components of the linearly polarized probing radiation. The capability of the method is enhanced by modulating the radiation polarization, which provided a reliable registration of stresses in the specimen at a temperature drop of about 0.1 K. The stress kinetics with a complicated behavior and ambiguous by sign is detected at the observation point within the temperature establishment time interval. Its modeling in terms of exponential functions made it possible to decompose the measurement results into components associated with the radiative, conductive, and convective heat transfer mechanisms, as well as determine their relaxation parameters. The measurement data can be of practical use while determining such technically important material characteristics as the thermal diffusion and heat transfer coefficients.

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Tada, Yuko, and Phillip C. Yang. "Iron Oxide Labeling and Tracking of Extracellular Vesicles." Magnetochemistry 5, no. 4 (November 7, 2019): 60. http://dx.doi.org/10.3390/magnetochemistry5040060.

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Extracellular vesicles (EVs) are essential tools for conveying biological information and modulating functions of recipient cells. Implantation of isolated or modulated EVs can be innovative therapeutics for various diseases. Furthermore, EVs could be a biocompatible drug delivery vehicle to carry both endogenous and exogenous biologics. Tracking EVs should play essential roles in understanding the functions of EVs and advancing EV therapeutics. EVs have the characteristic structures consisting of the lipid bilayer and specific membrane proteins, through which they can be labeled efficiently. EVs can be labeled either directly using probes or indirectly by transfection of reporter genes. Optical imaging (fluorescent imaging and bioluminescent imaging), single-photon emission computed tomography (SPECT)/positron emission tomography (PET), and magnetic resonance imaging (MRI) are currently used for imaging EVs. Labeling EVs with superparamagnetic iron oxide (SPIO) nanoparticles for MRI tracking is a promising method that can be translated into clinic. SPIO can be internalized by most of the cell types and then released as SPIO containing EVs, which can be visualized on T2*-weighted imaging. However, this method has limitations in real-time imaging because of the life cycle of SPIO after EV degradation. Further studies will be needed to validate SPIO labeling by other imaging modalities in preclinical studies. The emerging technologies of labeling and imaging EVs with SPIO in comparison with other imaging modalities are reviewed in this paper.

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Meng, Fanhui, Jun Li, Wenjun Wang, and Yan Fu. "Gengnianchun, a Traditional Chinese Medicine, Enhances Oxidative Stress Resistance and Lifespan in Caenorhabditis elegans by Modulating daf-16/FOXO." Evidence-Based Complementary and Alternative Medicine 2017 (2017): 1–10. http://dx.doi.org/10.1155/2017/8432306.

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Objective. Gengnianchun (GNC), a traditional Chinese medicine (TCM), is primarily used to improve declining functions related to aging. In this study, we investigated its prolongevity and stress resistance properties and explored the associated regulatory mechanism using a Caenorhabditis elegans model. Methods. Wild-type C. elegans N2 was used for lifespan analysis and oxidative stress resistance assays. Transgenic animals were used to investigate pathways associated with antioxidative stress activity. The effects of GNC on levels of reactive oxygen species (ROS) and expression of specific genes were examined. Results. GNC-treated wild-type worms showed an increase in survival time under both normal and oxidative stress conditions. GNC decreased intracellular ROS levels by 67.95%. GNC significantly enhanced the oxidative stress resistance of several mutant strains, suggesting that the protective effect of GNC is independent of the function of these genes. However, the oxidative stress resistance effect of GNC was absent in worms with daf-16 mutation. We also found upregulation of daf-16 downstream targets including sod-3 and mtl-1. Conclusions. Our findings suggest that GNC extends the lifespan of C. elegans and enhances its resistance to oxidative stress via a daf-16/FOXO-dependent pathway. This study also provides a feasible method for screening the biological mechanisms of TCMs.

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Gong, Xianghui, Xixi Zhao, Bin Li, Yan Sun, Meili Liu, Yan Huang, Xiaoling Jia, Jing Ji, and Yubo Fan. "Quantitative Studies of Endothelial Cell Fibronectin and Filamentous Actin (F-Actin) Coalignment in Response to Shear Stress." Microscopy and Microanalysis 23, no. 5 (September 12, 2017): 1013–23. http://dx.doi.org/10.1017/s1431927617012454.

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AbstractBoth fibronectin (FN) and filamentous actin (F-actin) fibers play a critical role for endothelial cells (ECs) in responding to shear stress and modulating cell alignment and functions. FN is dynamically coupled to the F-actin cytoskeleton via focal adhesions. However, it is unclear how ECs cooperatively remodel their subcellular FN matrix and intracellular F-actin cytoskeleton in response to shear stress. Current studies are hampered by the lack of a reliable and sensitive quantification method of FN orientation. In this study, we developed a MATLAB-based feature enhancement method to quantify FN and F-actin orientation. The role of F-actin in FN remodeling was also studied by treating ECs with cytochalasin D. We have demonstrated that FN and F-actin codistributed and coaligned parallel to the flow direction, and that F-actin alignment played an essential role in regulating FN alignment in response to shear stress. Our findings offer insight into how ECs cooperatively remodel their subcellular ECM and intracellular F-actin cytoskeleton in response to mechanical stimuli, and are valuable for vascular tissue engineering.

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Yeo, In-Seok, Yeo-Jin Yoon, Nari Seo, Hyun Joo An, and Jae-Han Kim. "Biopurification of Oligosaccharides by Immobilized Kluyveromyces Lactis." Applied Sciences 9, no. 14 (July 17, 2019): 2845. http://dx.doi.org/10.3390/app9142845.

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Oligosaccharides with diverse and complex structures such as milk oligosaccharides have physiological functions including modulating intestinal microbiota or stimulating immune cell responses. However, milk carbohydrates include about 40–50% of lactose which requires a cost-effective method to separate. We developed a new method to purify the oligosaccharides from carbohydrate mixtures such as human milk oligosaccharides (HMOs) and galactooligosaccharides (GOSs) by exploiting immobilized Kluyveromyces lactis as microbial catalysts. Evaluation of media components exhibited no significant differences in the lactose removal efficiency when nutrient-rich media, minimal salt media, and distilled water without any media components were used. With the immobilization on alginate beads, the lactose removal efficiency was increased 3.4 fold compared to that of suspension culture. When the immobilized cells were reused to design a continuous process, 4 h of pre-activation enhanced the lactose eliminating performance 2.5 fold. Finally, immobilized K. lactis was used as microbial catalysts for the biopurification of HMOs and GOSs, and lactose was effectively removed without altering the overall distribution of oligosaccharides.

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Chen, Xiao, Alex Morehead, Jian Liu, and Jianlin Cheng. "A gated graph transformer for protein complex structure quality assessment and its performance in CASP15." Bioinformatics 39, Supplement_1 (June 1, 2023): i308—i317. http://dx.doi.org/10.1093/bioinformatics/btad203.

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Abstract Motivation Proteins interact to form complexes to carry out essential biological functions. Computational methods such as AlphaFold-multimer have been developed to predict the quaternary structures of protein complexes. An important yet largely unsolved challenge in protein complex structure prediction is to accurately estimate the quality of predicted protein complex structures without any knowledge of the corresponding native structures. Such estimations can then be used to select high-quality predicted complex structures to facilitate biomedical research such as protein function analysis and drug discovery. Results In this work, we introduce a new gated neighborhood-modulating graph transformer to predict the quality of 3D protein complex structures. It incorporates node and edge gates within a graph transformer framework to control information flow during graph message passing. We trained, evaluated and tested the method (called DProQA) on newly-curated protein complex datasets before the 15th Critical Assessment of Techniques for Protein Structure Prediction (CASP15) and then blindly tested it in the 2022 CASP15 experiment. The method was ranked 3rd among the single-model quality assessment methods in CASP15 in terms of the ranking loss of TM-score on 36 complex targets. The rigorous internal and external experiments demonstrate that DProQA is effective in ranking protein complex structures. Availability and implementation The source code, data, and pre-trained models are available at https://github.com/jianlin-cheng/DProQA.

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Pang, Tianxiang, Qinghua Li, Jianxiang Wang, Wensu Yuan, Lei Zhang, and Zhongchao Han. "Effect of Roline Rich Domain of an RNA-Binding Protein Sam68 in B Lymphocyte Leukemia Cell Line Growth Process, Death and B Cell Signal Transduction." Blood 108, no. 11 (November 16, 2006): 4465. http://dx.doi.org/10.1182/blood.v108.11.4465.4465.

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Abstract Sam68 plays an important role as a multiple functional RNA binding nuclear protein in cell cycle progress, RNA usage, signal transduction regulation of cell growth and proliferation, and tyrosine phosphorylation by Src during mitosis. However, its precise impact on these essential cellular functions remains unclear. The purpose of this study is to further elucidate Sam68 functions in B lymphocyte leukemia DT40 cell line. By using gene targeting method, we isolated a mutation of deleted proline rich domain from Sam68 in DT40 cells and described its effect on cell growth process and signal transduction. The results have demonstrated that mutant cells grew at a slower rate (2.1 hours growth elongation). Cell cycle pattern was observed in mutant cells by flow-cytometric analysis, the retardation of cell growth was mainly due to the elongation of S phase (1.7 hours elongation). When the cell cycle was analyzed at different serum concentration conditions, we found that the effect of Sam68 mutant on the S phase was further supported by the serum depletion experiment. In light of evidence that RNA binding activity is essential for functions, Sam68 is implicated in cell growth control probably by modulating the function of mRNAs in S phase or earlier. Larger amounts of dead cells was observed in the culture of mutant cells, and serum depletion enhanced the ratio of dead cells in both culture conditions. Since the putative control of cell cycle by Sam68 appeared to be related to signal transduction, we next assessed the involvement of Sam68 in B cell signal transduction pathway. After cross-linking of B cell receptor on the DT40 cells by IgM antibody, phosphorylation of cellular proteins was analyzed by protein blotting with anti-phosphotyrosine antibody. The result demonstrated that the overall pattern of B cell receptor in Sam68 mutant cells was similar to that in the wild type DT40 cells. However, the maximal level of tyrosine phosphorylation on BLNK, a prominent signal molecule in B cell, has been observed no significantly changes in the mutant cells. Since the expression levels of B cell receptor on the Sam68 mutation clones were essentially same as that of parental DT40 cells, it was suggested that deletion of partial of proline region in Sam68 resulted in the decrease in B cell signal transduction. We have concluded that the proline rich domain of Sam68 is involved in cell growth control by modulating the function of mRNAs in S phase or earlier and the functions as an adaptor molecule in B cell signal transduction pathways.

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Sun, Eryi, and Ping Zhang. "RNF12 Promotes Glioblastoma Malignant Proliferation via Destructing RB1 and Regulating MAPK Pathway." Journal of Healthcare Engineering 2021 (November 30, 2021): 1–8. http://dx.doi.org/10.1155/2021/4711232.

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Background. RNF12 has been linked to a variety of biological activities, including the control of the MDM2/P53 pathway, although its additional functions remain unclear. RNF12 was discovered to be a new ubiquitin ligase (E3) for RB1, amongst the most frequently repressed proteins in cancer of human. Method. Cell Counting Kit-8 was used to detect the cell proliferation; coimmunoprecipitation was used to determine that RNF12 interacts with RB1. Xenograft studies were used to verify the results. Result. In vivo and in vitro RNF12 interacts with RB1 regardless of E3 ligase activity. The ubiquitination of RB1 by RNF12 had an effect on its stability. RNF12 inhibits the RB1 protein and stimulates the MAPK pathway, promoting the growth of GBMs. Conclusion. Our findings show that RNF12 may operate as a tumour promoter by modulating the cancerous proliferation of glioblastoma by controlling the activity of a new RNF12/RB1/MAPK pathway regulatory axis and that this regulatory axis might be a valuable diagnostic focus in glioblastoma.

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Bhatt, Megha, Prafull Salvi, and Pushpa Lohani. "Gateway cloning and in-planta transformation of drought stress responsive Ecmyb1 gene isolated from Eleusine coracana var.PRM 6107." Environment Conservation Journal 22, no. 1&2 (June 19, 2021): 205–11. http://dx.doi.org/10.36953/ecj.2021.221229.

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Drought is one of the key abiotic stress that critically influences the crops by restraining their growth and yield potential. Being sessile, plants tackle the detrimental effects of drought stress via modulating the cellular state by changing the gene expression. Such alteration of gene expression is essentially driven by the transcriptional syndicate. Transcription factors (TF) are the key regulatory protein that controls the expression of their target gene by binding to the cis-regulatory elements present in the promoter region. Myb-TFs ubiquitously present in all eukaryotes belong to one of the largest TF family, and play wide array of biological functions in plants including anthocyanin biosynthesis, vasculature system, cell signaling, seed maturation and abiotc stress responses. In the present study the full length Myb TF from Eleusine corocana was subcloned using Gateway cloning system and further transformed into Arabidopsis thaliana through floral dip method. Transgenic Arabidopsis thaliana plants harbouring Ecmyb1 gene were screened and grown in transgenic glasshouse under controlled conditions.

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Giddens, John P., Joseph V. Lomino, David J. DiLillo, Jeffrey V. Ravetch, and Lai-Xi Wang. "Site-selective chemoenzymatic glycoengineering of Fab and Fc glycans of a therapeutic antibody." Proceedings of the National Academy of Sciences 115, no. 47 (November 5, 2018): 12023–27. http://dx.doi.org/10.1073/pnas.1812833115.

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The N-glycans attached to the Fab and Fc domains play distinct roles in modulating the functions of antibodies. However, posttranslational site-selective modifications of glycans in antibodies and other multiply glycosylated proteins remain a challenging task. Here, we report a chemoenzymatic method that permits independent manipulation of the Fab and Fc N-glycans, using cetuximab as a model therapeutic monoclonal antibody. Taking advantage of the substrate specificity of three endoglycosidases (Endo-S, Endo-S2, and Endo-F3) and their glycosynthase mutants, together with an unexpected substrate site-selectivity of a bacterial α1,6-fucosidase from Lactobacillus casei (AlfC), we were able to synthesize an optimal homogeneous glycoform of cetuximab in which the heterogeneous and immunogenic Fab N-glycans were replaced with a single sialylated N-glycan, and the core-fucosylated Fc N-glycans were remodeled with a nonfucosylated and fully galactosylated N-glycan. The glycoengineered cetuximab demonstrated increased affinity for the FcγIIIa receptor and significantly enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) activity.

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Hou, Mingming, Jiu Hui Wu, Songhua Cao, Dong Guan, and Yanwei Zhu. "Extremely low frequency band gaps of beam-like inertial amplification metamaterials." Modern Physics Letters B 31, no. 27 (September 28, 2017): 1750251. http://dx.doi.org/10.1142/s0217984917502517.

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In this paper, extremely low frequency band gaps of beam-like inertial amplification metamaterials are investigated based on local resonance theory. Inertial amplification mechanism is proposed to obtain extremely low frequency band gaps by altering geometry parameters of the beam-like structures rather than modulating material properties, which allow first lower band gap (BG) to be attained easily compared to traditional local resonance structures. Band structures, frequency response functions (FRFs) plots and vibration modes of the beam-like structures are calculated and analyzed by employing finite element method. Numerical results show that first BG of the structure ranges from 23 Hz to 21 Hz. FRFs are in accordance with the dispersion relationship. It is found that interaction between inertial amplification and traveling wave modes in the proposed structure are responsible for formation of the first BG. This type of beam-like inertial amplification metamaterials has many potential applications in the field of low frequency vibration and noise reduction.

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Benigni, Valentina. "È stato un mezzo disastro… Fenomeni di convergenza tra approssimazione e intensificazione: uno studio contrastivo su italiano e russo." Italica Wratislaviensia 14, no. 1 (2023): 9–34. http://dx.doi.org/10.15804/iw.2022.14.1.01.

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Based on the case-study of the Italian downtoner mezzo, ‘half of’, the present work aims to highlight, through a usage-based approach, interesting points of semantic and functional convergence between approximation and intensification, which are traditionally considered divergent meaningconstruction strategies. Mezzo functions both on the semantic level, by modulating the referential force of nouns, verbs, and adjectives, and on the pragmatic level, where it acts as a discourse marker, enabling the speaker to reduce the illocutionary force of their assertions and helping the receiver to make the inferences necessary to recognise the speaker’s communicative intentions in cases of “loose talk” (in Relevance Theory terms), such as understatement and overstatement. In the second part of the article, the results of a contrastive analysis with Russian are discussed, based on the assumption that the identification of functional equivalences between different languages is a valid heuristic method to explain the semantic and pragmatic multifunctionality of certain lexical elements, also from a cross-linguistic perspective.

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He, J., and D. J. Marsh. "Effect of captopril on fluctuations of blood pressure and renal blood flow in rats." American Journal of Physiology-Renal Physiology 264, no. 1 (January 1, 1993): F37—F44. http://dx.doi.org/10.1152/ajprenal.1993.264.1.f37.

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Arterial blood pressure and renal blood flow (RBF) fluctuations in rats were studied by autoregressive (AR) and autoregressive-moving average (ARMA) modeling. These estimation procedures provided greater sensitivity and frequency resolution than classic fast Fourier transform (FFT)-based methods and also require shorter observation periods. We estimated the transfer function of RBF autoregulation to test whether inhibition of angiotensin-converting enzyme impairs whole kidney dynamic autoregulation. The transfer function in control animals measured with the ARMA method was similar to transfer functions obtained previously, using FFT methods. Because of better frequency resolution, we also detected an oscillation in RBF at 50 mHz, the same frequency as an oscillation in tubular pressure and glomerular filtration rate that had been attributed to tubuloglomerular feedback (TGF), but that FFT methods had not previously found in whole kidney blood flow. Captopril increased the amplitude of RBF fluctuations and increased the gain of the transfer function at frequencies below 100 mHz, a frequency bandwidth previously associated with TGF. The increased gain indicates that TGF operates less effectively to mediate dynamic autoregulation when angiotensin conversion is inhibited. Gain at frequencies greater than 100 mHz, previously ascribed to the myogenic mechanism, was not affected by captopril. These results show that angiotensin, by modulating TGF, reduces fluctuations of RBF about the mean value.

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Yeom, Seon-In, Hyang-Ku Baek, Sang-Keun Oh, Won-Hee Kang, Sang Jik Lee, Je Min Lee, Eunyoung Seo, Jocelyn K. C. Rose, Byung-Dong Kim, and Doil Choi. "Use of a Secretion Trap Screen in Pepper Following Phytophthora capsici Infection Reveals Novel Functions of Secreted Plant Proteins in Modulating Cell Death." Molecular Plant-Microbe Interactions® 24, no. 6 (June 2011): 671–84. http://dx.doi.org/10.1094/mpmi-08-10-0183.

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In plants, the primary defense against pathogens is mostly inducible and associated with cell wall modification and defense-related gene expression, including many secreted proteins. To study the role of secreted proteins, a yeast-based signal-sequence trap screening was conducted with the RNA from Phytophthora capsici-inoculated root of Capsicum annuum ‘Criollo de Morelos 334’ (CM334). In total, 101 Capsicum annuum secretome (CaS) clones were isolated and identified, of which 92 were predicted to have a secretory signal sequence at their N-terminus. To identify differences in expressed CaS genes between resistant and susceptible cultivars of pepper, reverse Northern blots and real-time reverse-transcription polymerase chain reaction were performed with RNA samples isolated at different time points following P. capsici inoculation. In an attempt to assign biological functions to CaS genes, we performed in planta knock-down assays using the Tobacco rattle virus-based gene-silencing method. Silencing of eight CaS genes in pepper resulted in suppression of the cell death induced by the non-host bacterial pathogen (Pseudomonas syringae pv. tomato T1). Three CaS genes induced phenotypic abnormalities in silenced plants and one, CaS259 (PR4-l), caused both cell death suppression and perturbed phenotypes. These results provide evidence that the CaS genes may play important roles in pathogen defense as well as developmental processes.

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Hu, Peng, Fei Zhang, Yan Han, and Naijie Yan. "Characteristics of Fluctuating Wind Speed Spectra of Moving Vehicles under the Non-Stationary Wind Field." Sustainability 15, no. 17 (August 25, 2023): 12901. http://dx.doi.org/10.3390/su151712901.

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To promote energy saving, emission reduction, and sustainable development of high-speed trains, as well as achieve low-carbon operation of these trains. It is necessary to establish a fluctuating wind speed spectra model that can accurately describe the characteristics of the fluctuating wind speed field of the moving vehicle. This will help explore the effects of strong winds on the running resistance, energy consumption, safety, and comfort of trains. In this paper, based on Priestley’s evolutionary power spectral density (EPSD) theory, an efficient method was developed for generating the fluctuating wind speeds at the moving point under the non-stationary wind field. On such basis, the effects of different mean wind speeds, ground clearances, temporal modulation function parameters, and vehicle’s moving speeds on the time-varying correlation function ratio of fluctuating wind speed at fixed and moving points were analyzed. Subsequently, the relationship between the time-varying correlation functions of fluctuating wind speed at the fixed and moving points was established by analyzing the sensitivity of the above parameters, and a theoretical model of fluctuating wind speed spectra of the moving point under the non-stationary wind field was proposed. In addition, the relational expression of fluctuating wind speed spectra of the moving point under stationary and non-stationary wind fields was established, which was further validated using the fluctuating wind speed spectra model at the fixed points with different modulation function forms. The results demonstrated that the direct generation method can avoid n times of POD decomposition and Ns∑j=1nNqjj times of FFT calculation, improve the calculation speed, and save memory. The proposed fluctuating wind speed spectra model at the moving point under the non-stationary wind field is in good agreement with the corresponding target one, indicating the high accuracy of the proposed model. Meanwhile, it is also noted that the fluctuating wind speed spectra at the moving point under the non-stationary wind field can be obtained by modulating the spectra under the stationary wind field using temporal modulation function, which is the same as that of the fluctuating wind speed spectra at fixed points under the non-stationary wind field.

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Awasthi, Vineet, L. Vijaya Mohan Rao, and Usha Pendurthi. "Modulation of Tissue Factor-Factor VIIa Coagulant and Signaling Functions by Membrane Cholesterol and Caveolae." Blood 104, no. 11 (November 16, 2004): 2627. http://dx.doi.org/10.1182/blood.v104.11.2627.2627.

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Abstract Cholesterol in the membrane not only regulates flexibility and mechanical stability of the membrane but also plays a critical role in differentiating and maintaining cell surface microdomains of differing lipid composition, particularly sphingolipid rafts. Cholesterol- and sphingolipid-rich rafts in association with a structural protein, caveolin, form caveolae, flask-shaped invaginations in the plasma membrane. Lipid rafts and caveolae are shown to regulate various cellular functions, including receptor function, endocytosis, intracellular trafficking of receptors and signaling pathways. In the present study, we investigated the role of membrane cholesterol and caveolae in modulating coagulant and signaling functions of tissue factor (TF)-factor VIIa (VIIa) complexes on tumor cells. Breast carcinoma cells, MDA-MB-231, were treated with ß-methyl cyclodextrin (CD), which depletes membrane cholesterol and thereby disrupts caveolae, or with filipin, which disrupts caveolae without depleting the membrane cholesterol. TF-VIIa coagulant function was measured in factor X activation assay and the signaling function was evaluated in IP3 hydrolysis and IL-8 gene induction. As expected, CD (10 mM) treatment of tumor cells depleted cellular cholesterol level by more than 70% whereas filipin (5 μg/ml) treatment did not reduce the cellular cholesterol level. Both the treatments had no effect on the cell viability as measured in trypan blue exclusion method and MTT assay. CD treatment, in a dose-pendent manner (1 to 10 mM CD), impaired both TF-VIIa coagulant function and the signaling function (both IP3 hydrolysis and IL-8 gene expression). In contrast, varying effects were observed with filipin treatment. Filipin treatment (5 μg/ml) increased TF-VIIa coagulant function, reduced the TF-VIIa-induced IP3 hydrolysis and no effect on TF-VIIa-induced IL-8 gene expression. Detergent (Triton X-100) extraction of cells followed by fractionation on sucrose gradient centrifugation showed that TF was distributed both in lipid rafts and soluble fractions. CD and filipin treatments slightly reduced TF association with lipid rafts. Overall these data suggest that the membrane cholesterol modulates TF-VIIa proteolytic function and hence the TF-VIIa protease-induced signaling. In contrast, disruption of caveolae uncouples selective signaling pathways activated by TF-VIIa without impairing TF-VIIa protease activity.

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Kahoul, Yasmina, Xi Yao, Frédérik Oger, Maeva Moreno, Souhila Amanzougarene, Mehdi Derhourhi, Emmanuelle Durand, et al. "Knocking Down CDKN2A in 3D hiPSC-Derived Brown Adipose Progenitors Potentiates Differentiation, Oxidative Metabolism and Browning Process." Cells 12, no. 6 (March 10, 2023): 870. http://dx.doi.org/10.3390/cells12060870.

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Human induced pluripotent stem cells (hiPSCs) have the potential to be differentiated into any cell type, making them a relevant tool for therapeutic purposes such as cell-based therapies. In particular, they show great promise for obesity treatment as they represent an unlimited source of brown/beige adipose progenitors (hiPSC-BAPs). However, the low brown/beige adipocyte differentiation potential in 2D cultures represents a strong limitation for clinical use. In adipose tissue, besides its cell cycle regulator functions, the cyclin-dependent kinase inhibitor 2A (CDKN2A) locus modulates the commitment of stem cells to the brown-like type fate, mature adipocyte energy metabolism and the browning of adipose tissue. Here, using a new method of hiPSC-BAPs 3D culture, via the formation of an organoid-like structure, we silenced CDKN2A expression during hiPSC-BAP adipogenic differentiation and observed that knocking down CDKN2A potentiates adipogenesis, oxidative metabolism and the browning process, resulting in brown-like adipocytes by promoting UCP1 expression and beiging markers. Our results suggest that modulating CDKN2A levels could be relevant for hiPSC-BAPs cell-based therapies.

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Szpakowski, Piotr, Dominika Ksiazek-Winiarek, Joanna Czpakowska, Mateusz Kaluza, Marta Milewska-Jedrzejczak, and Andrzej Glabinski. "Astrocyte-Derived Exosomes Differentially Shape T Cells’ Immune Response in MS Patients." International Journal of Molecular Sciences 24, no. 8 (April 18, 2023): 7470. http://dx.doi.org/10.3390/ijms24087470.

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Astrocytes, the most abundant group of glia cells in the brain, provide support for neurons and indicate multiple various functions in the central nervous system (CNS). Growing data additionally describe their role in the regulation of immune system activity. They exert their function not only by direct contact with other cell types, but also through an indirect method, e.g., by secreting various molecules. One such structure is extracellular vesicles, which are important mediators of crosstalk between cells. In our study, we observed that the impact of exosomes derived from astrocytes with various functional phenotype differently affect the immune response of CD4+ T cells, both from healthy individuals and from patients with multiple sclerosis (MS). Astrocytes, by modulating exosome cargo, impacts the release of IFN-γ, IL-17A and CCL2 in our experimental conditions. Considering the proteins concentration in cell culture supernatants and the cellular percentage of Th phenotypes, it could be stated that human astrocytes, by the release of exosomes, are able to modify the activity of human T cells.

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Liu Yifan, 刘一凡, 胡以华 Hu Yihua, 张鑫源 Zhang Xinyuan, 王一程 Wang Yicheng, 韩飞 Han Fei, 徐世龙 Xu Shilong, and 董骁 Dong Xiao. "基于调制传递函数的激光反射层析成像质量评价方法." Chinese Journal of Lasers 50, no. 6 (2023): 0610001. http://dx.doi.org/10.3788/cjl220757.

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Zhang Weiguang, 张维光, 于洵 Yu Xun, 韩峰 Han Feng, 张发强 Zhang Faqiang, 吴银花 Wu Yinhua, and 陈玉娇 Chen Yujiao. "室内模拟环境下动态调制传递函数检测方法." Infrared and Laser Engineering 51, no. 7 (2022): 20210756. http://dx.doi.org/10.3788/irla20210756.

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Journal articles on the topic 'Modulating functions method'

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