Journal articles: 'DPFC'

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Parackal, Bhavana, Hamidreza Khakdaman, Yves Bourgault, and Marten Ternan. "An Investigation of Direct Hydrocarbon (Propane) Fuel Cell Performance Using Mathematical Modeling." International Journal of Electrochemistry 2018 (December 2, 2018): 1–18. http://dx.doi.org/10.1155/2018/5919874.

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An improved mathematical model was used to extend polarization curves for direct propane fuel cells (DPFCs) to larger current densities than could be obtained with any of the previous models. DPFC performance was then evaluated using eleven different variables. The variables related to transport phenomena had little effect on DPFC polarization curves. The variables that had the greatest influence on DPFC polarization curves were all related to reaction rate phenomena. Reaction rate phenomena were dominant over the entire DPFC polarization curve up to 100 mA/cm2, which is a value that approaches the limiting current densities of DPFCs. Previously it was known that DPFCs are much different than hydrogen proton exchange membrane fuel cells (PEMFCs). This is the first work to show the reason for that difference. Reaction rate phenomena are dominant in DPFCs up to the limiting current density. In contrast the dominant phenomenon in hydrogen PEMFCs changes from reaction rate phenomena to proton migration through the electrolyte and to gas diffusion at the cathode as the current density increases up to the limiting current density.

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Chakravorty, J., and J. Saraswat. "Deciding Optimal Location of DPFC in Transmission Line Using Artificial Algae Algorithm." Engineering, Technology & Applied Science Research 9, no. 2 (April 10, 2019): 3978–80. http://dx.doi.org/10.48084/etasr.2667.

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In this paper, the application of artificial algae algorithm (AAA) in optimal placement distributed power flow controller (DPFC) with MCFC in transmission networks has been proposed The proposed method is tested on IEEE 14- bus system and the results are discussed. The biggest advantage of DPFC is that it can control the active and reactive power flow and bus voltages, simultaneously. In this paper, the optimal placement of one DPFC in IEEE-14 bus system and then optimal placement of two DPFCs in IEEE-14 bus system has been proposed. Optimal placement of DPFC in power system by AAA leads to increased stability and capacity of the power transmission in lines. The proposed model has been simulated in Matlab/Simulink and the performance results are tabulated.

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Ajami, Ali, Behrouz Soulat, and Amin Safari. "A Novel Modelling and Controlling of Distributed Power Flow Controller (DPFC) Base on PSO Algorithm." ECTI Transactions on Electrical Engineering, Electronics, and Communications 11, no. 1 (July 9, 2012): 1–8. http://dx.doi.org/10.37936/ecti-eec.2013111.170576.

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This paper focuses mainly on the state modelling controlling of a new FACTS device named Distributed Power Flow Controller (DPFC). The paper also discusses the role and function of DPFC in power ﬂow controlling together with its economic evaluation. DPFC is one of the Distributed FACTS (D-FACTS) devices. Its function is similar to that of UPFC but instead of one series converters, several low power series converters are used in DPFC. Therefore, DPFC includes multiple series converters and one shunt converter without common dc link. This eventually enables the DPFC to fully control all power system parameters. It, also, increases the reliability of the device and reduces its cost simultaneously. In this study a novel current injection model of DPFC is presented. The suggested model is suitable for steady state and stability studies. To use the presented model, a proper control system is needed. In this paper the PSO algorithm is used for optimal designing of controller parameters. Application of DPFC in diﬀerent operating conditions and failure in series converters are simulated with Matlab/Simulink software .The presented control system enables the DPFC to control the active and reactive power ﬂow at the transmission line independently. In conclusion, the resented simulation results show the validity and eﬀectiveness of suggested modelling and control system of DPFC for power ﬂow controlling.

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Shende, Mahesh. "Improvement of Power Quality in Distribution System using Photovoltaic based DPFC." International Journal for Research in Applied Science and Engineering Technology 9, no. VI (June 15, 2021): 1038–42. http://dx.doi.org/10.22214/ijraset.2021.35049.

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In Modern Power System power quality is the main issue of the power companies. Improvement of power quality in distribution system using photovoltaic based DPFC is declared in this paper. Flexible AC Transmission System (FACTS) device which is known as distributed power flow controller (DPFC)is used. DPFC is derived from UPFC by eliminating common dc link between series and shunt converter. Unified power flow controller (UPFC) is widely used and control all parameters of the system. The UPFC handle the current and voltage with high rating; therefore, the cost of system is high. Therefore, distributed power flow controller (DPFC) is used due to high control capability, high Reliability & low cost. DPFC also measures the transmission angle, line impedance and bus voltage. In distribution system problems occur like voltage sag/swell, Harmonics etc. Photovoltaic system is used as source for DPFC.

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Bahamani, Akhib Khan, G. M. Sreerama Reddy, and V. Ganesh. "Voltage Stability Improvement in Fourteen Bus System during Line Interruption using DPFC." International Journal of Power Electronics and Drive Systems (IJPEDS) 8, no. 2 (June 1, 2017): 705. http://dx.doi.org/10.11591/ijpeds.v8.i2.pp705-711.

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DPFC is proposed in the present work to improve voltage stability of fourteen bus system during line interruption. The voltage across the load decreases due to the interruption of the line. State space method is used to calculate Line currents and bus voltages. The ability of DPFC to bring voltage, real power and reactive power to normal level is presented in this paper. The simulation results for healthy system, line interrupted system without DPFC and with DPFC are presented. The results of comparative study are presented to show the improvement in power quality. The simulation studies indicate that the power flow with DPFC during line outage is almost equal to the power during healthy condition.

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Bahamani, Akhib Khan, G. M. Sreerama Reddy, and V. Ganesh. "Power Quality Improvement in Fourteen Bus System using Non-Conventional Source Based ANN Controlled DPFC System." Indonesian Journal of Electrical Engineering and Computer Science 4, no. 3 (December 18, 2016): 499. http://dx.doi.org/10.11591/ijeecs.v4.i3.pp499-507.

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DPFC can be used to improve receiving end voltage of fourteen bus system. This paper shows the conception and simulation of wind and solar based distribution power flow controller for sag compensation and ohmic loss reduction. The objectives of this work are to improve the voltage and reduce the line losses. Fourteen bus systems with DPFC in open loop is simulated. Fourteen bus system with DPFC in closed loop using PI and ANN are also simulated and the results are presented. The comparative study is presented to demonstrate the improvement in dynamic response of ANN controlled DPFC system. ANN is observed to provide better control than has other controllers and improved damping characterises.

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Tao, Qingsong, Jianan Ren, Zhenling Ji, Shengli Liu, Baochai Wang, Yu Zheng, Guosheng Gu, Xinbo Wang, and Jieshou Li. "VAWCM-Instillation Improves Delayed Primary Fascial Closure of Open Septic Abdomen." Gastroenterology Research and Practice 2014 (2014): 1–7. http://dx.doi.org/10.1155/2014/245182.

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Background.Failure to achieve delayed primary fascial closure (DPFC) is one of the main complications of open abdomen (OA), certainly when abdominal sepsis is present. This retrospective cohort study aims to evaluate the effect of combined therapy of vacuum-assisted mesh-mediated fascial traction and topical instillation (VAWCM-instillation) on DPFC in the open septic abdomen.Methods.The patients with abdominal sepsis who underwent OA using VAWCM were included and divided into the instillation and noninstillation (control) groups. The DPFC rate and other outcomes were compared between the two groups.Results.Between 2007 and 2013, 73 patients with open septic abdomen were treated with VAWCM-instillation and 61 cases with VAWCM-only. The DPFC rate in the instillation group was significantly increased (63% versus 41%,P=0.011). The mortality with OA was similar (24.6% versus 23%,P=0.817) between the two groups. However, time to DPFC(P=0.003)and length of stay in hospital(P=0.022)of the survivals were significantly decreased in the instillation group. In addition, VAWCM-instillation (OR 1.453, 95% CI 1.222–4.927,P=0.011) was an independent influencing factor related to successful DPFC.Conclusions.VAWCM-instillation could improve the DPFC rate but could not decrease the mortality in the patients with open septic abdomen.

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C, Subramani, S. S. Dash, Vimala C, and Uma Mageshwari. "Impact of Distributed Power Flow Controller to Improve Line Flow Based on PWM Control with PI Technique." Indonesian Journal of Electrical Engineering and Computer Science 4, no. 1 (November 4, 2016): 57. http://dx.doi.org/10.11591/ijeecs.v4.i1.pp57-64.

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In this paper we presents a new component within the flexible ac-transmission system (FACTS) family, called Distributed Power-Flow Controller (DPFC). The DPFC is derived from the unified power-flow controller (UPFC). The DPFC can be considered as a UPFC with an eliminated common dc link. The active power exchange between the shunt and series converters, which is through the common dc link in the UPFC, is now through the transmission lines at the third-harmonic frequency. The DPFC employs the distributed FACTS (DFACTS) concept, which is to use multiple small-size single-phase converters instead of the one large-size three-phase series converter in the UPFC. The large number of series converters provides redundancy, thereby increasing the system reliability. As the D-FACTS converters are single-phase and floating with respect to the ground, there is no high-voltage isolation required between the phases. Accordingly, the cost of the DPFC system is lower than the UPFC. The DPFC has the same control capability as the UPFC, which comprises the adjustment of the line impedance, the transmission angle, and the bus voltage. The controller is designed to achieve the most appropriate operating point based on the real power priority.

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Saini, Kuldeep, Aakash Saxena, and M. R. Farooqi. "Analysis of Distributed Power Flow Controller in Power System Network for Improving Power Flow Control." Indonesian Journal of Electrical Engineering and Computer Science 2, no. 3 (June 1, 2016): 510. http://dx.doi.org/10.11591/ijeecs.v2.i3.pp510-521.

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In this paper, a new power flow controlling device called Distributed Power Flow Controller (DPFC) is presented that offers the same control capability as the unified power-flow controller (UPFC) but with much lower cost and high reliability. The DPFC eliminates the common DC link within the UPFC, to enable the independent operation of the shunt and the series converter. The D-FACTS concept is employed to the series converter to increase the reliability. Multiple low-rating single-phase converters replace the high-rating three-phase series converter, which significantly reduces the cost and increases the reliability. The active power that is exchanged through the common DC link in the UPFC is now transferred through the transmission line at the 3rd harmonic frequency. The DPFC is modeled in a rotating dq-frame. The modeling and analysis of DPFC in a two area two bus interconnected system is done in MATLAB/Simulink environment and comparison between the DPFC and UPFC considering the power flow and cost are also shown.

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Chakravorty, J., J. Saraswat, and V. Bhatia. "Modeling a Distributed Power Flow Controller with a PEM Fuel Cell for Power Quality Improvement." Engineering, Technology & Applied Science Research 8, no. 1 (February 20, 2018): 2585–89. http://dx.doi.org/10.48084/etasr.1807.

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Electrical power demand is increasing at a relatively fast rate over the last years. Because of this increasing demand the power system is becoming very complex. Both electric utilities and end users of electric power are becoming increasingly concerned about power quality. This paper presents a new concept of distributed power flow controller (DPFC), which has been implemented with a proton exchange membrane (PEM) fuel cell. In this paper, a PEM fuel cell has been simulated in Simulink/MATLAB and then has been used in the proposed DPFC model. The new proposed DPFC model has been tested on a IEEE 30 bus system.

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Vijaya Krishna, B., B. Venkata Prashanth, and P. Sujatha. "Design and implementation of DPFC for multi-bus power system." International Journal of Engineering & Technology 7, no. 2.8 (March 19, 2018): 18. http://dx.doi.org/10.14419/ijet.v7i2.8.10318.

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In current days, the power quality issues in the interconnected power system are mainly happens due to the demand of electricity and utilization of large non-linear loads as well as inductive/capacitive loads. The power quality cries are voltage sag and swell in multi-bus power system (MBPS). In this article studies on a two bus, three bus and five bus power systems using DPFC. In order to eliminate the voltage sag and swell in the MBPS, a distributed power flow controller (DPFC) is designed. The structure of the DPFC consists of three-phase shunt converter and three single series phase converters. Both these converters are arranged in back-back voltage source inverters (VSIs). These converters are controlled with help of the pulse width modulation (PWM) scheme. The feedback controllers and reference signals are derived the PWM for DPFC to magnify the power quality problems in MBPS. The performance of the model is investigated at different loads by making of MATLAB/Simulink model. The simulation results are presented.

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Rao, D. Narasimha, T. Surendra, and S. Tara Kalyani. "DPFC Performance with the Comparison of PI and ANN Controller." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 5 (October 1, 2016): 2080. http://dx.doi.org/10.11591/ijece.v6i5.11494.

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Modern power systems demand the active control of power flow and for this purpose Power flow controlling devices (PFCDs) are required. Distributed FACTS Controller (DPFC) is a part of FACTS family. DPFC offers equal control ability same as UPFC, comprising the adjustment of the internal angle of the machine and bus voltage includes line impedance. In addition to UPFC a new device evolved known as DPFC in which common DC link is eliminated that enables the exclusive working between the two converters which are shunt and the series. The Distributed-FACTS (D- FACTS) idea is adopt in the series converter scheme. The replacement of the high rating three phase series converter with the multiple low rating single phase converters results in cost reduction and increases reliability greatly. The useful power transfer between the two converters which are shunt and series through common dc link in UPFC where as in DPFC in this the required power is transferred in the transmission line with three times of natural fundamental frequency. Where as in the new device no need of large voltage separation between the line and PFC Device is no requirement of high voltage isolation between because D-FACTS converters which are 1-ᴓ floating device with respect to the ground. Accordingly, In this paper we bring out the DPFC performance differences with different control techniques which are PI and Artificial Neural Network Controllers and bring with conclusion that ANN is a better control strategy compared to PI.

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Rao, D. Narasimha, T. Surendra, and S. Tara Kalyani. "DPFC Performance with the Comparison of PI and ANN Controller." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 5 (October 1, 2016): 2080. http://dx.doi.org/10.11591/ijece.v6i5.pp2080-2087.

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Modern power systems demand the active control of power flow and for this purpose Power flow controlling devices (PFCDs) are required. Distributed FACTS Controller (DPFC) is a part of FACTS family. DPFC offers equal control ability same as UPFC, comprising the adjustment of the internal angle of the machine and bus voltage includes line impedance. In addition to UPFC a new device evolved known as DPFC in which common DC link is eliminated that enables the exclusive working between the two converters which are shunt and the series. The Distributed-FACTS (D- FACTS) idea is adopt in the series converter scheme. The replacement of the high rating three phase series converter with the multiple low rating single phase converters results in cost reduction and increases reliability greatly. The useful power transfer between the two converters which are shunt and series through common dc link in UPFC where as in DPFC in this the required power is transferred in the transmission line with three times of natural fundamental frequency. Where as in the new device no need of large voltage separation between the line and PFC Device is no requirement of high voltage isolation between because D-FACTS converters which are 1-ᴓ floating device with respect to the ground. Accordingly, In this paper we bring out the DPFC performance differences with different control techniques which are PI and Artificial Neural Network Controllers and bring with conclusion that ANN is a better control strategy compared to PI.

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Rao, D. Narasimha, T. Surnedra, and S. Tara Kalyani. "Improved Performance of DPFC Using Sliding Mode Controller Method." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 5 (October 1, 2016): 2073. http://dx.doi.org/10.11591/ijece.v6i5.11493.

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Modern power systems demand the need of active power flow with the help of Power Electronics control devices is needed. In the family of Flexible AC Transmission devices (FACTS), Dynamic PFC (DPFC) offers the same controlling function as Unified PFC (UPFC), comprising the control of transmission angle, bus voltage and line impedance. A technical modification of UPFC is DPFC in which fluctuations of voltage at DC link is eliminated that enables the individual operation as series and parallel controllers. The concept of DFACTS is used in design of the series converter. The replacement of the high rating three phase series converter with the multiple low rating single phase converters results in cost reduction and increases reliability greatly. This DC Link is used to transfer the real power between two converters in UPFC such as in DPFC which eliminates the 3rd harmonic frequencies at transmission lines. D-FACTS converters are acting as insulation between high voltage phases acts as 1-ᴓ floating with respect to ground. These results in lower cost for the DPFC system compared to the UPFC. This paper describes the comparison of PI and Sliding Mode Controllers which conclude that SMC is a better control strategy compared to PI.

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Rao, D. Narasimha, T. Surnedra, and S. Tara Kalyani. "Improved Performance of DPFC Using Sliding Mode Controller Method." International Journal of Electrical and Computer Engineering (IJECE) 6, no. 5 (October 1, 2016): 2073. http://dx.doi.org/10.11591/ijece.v6i5.pp2073-2079.

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Modern power systems demand the need of active power flow with the help of Power Electronics control devices is needed. In the family of Flexible AC Transmission devices (FACTS), Dynamic PFC (DPFC) offers the same controlling function as Unified PFC (UPFC), comprising the control of transmission angle, bus voltage and line impedance. A technical modification of UPFC is DPFC in which fluctuations of voltage at DC link is eliminated that enables the individual operation as series and parallel controllers. The concept of DFACTS is used in design of the series converter. The replacement of the high rating three phase series converter with the multiple low rating single phase converters results in cost reduction and increases reliability greatly. This DC Link is used to transfer the real power between two converters in UPFC such as in DPFC which eliminates the 3rd harmonic frequencies at transmission lines. D-FACTS converters are acting as insulation between high voltage phases acts as 1-ᴓ floating with respect to ground. These results in lower cost for the DPFC system compared to the UPFC. This paper describes the comparison of PI and Sliding Mode Controllers which conclude that SMC is a better control strategy compared to PI.

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Srinivasarao, Budi, G. Sreenivasan, and Swathi Sharma. "A Neuro-Fuzzy Controller for Compensation of Voltage Disturbance in SMIB System." Indonesian Journal of Electrical Engineering and Computer Science 5, no. 1 (January 1, 2017): 72. http://dx.doi.org/10.11591/ijeecs.v5.i1.pp72-80.

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Since last decade, due to advancement in technology and increasing in the electrical loads and also due to complexity of the devices the quality of power distribution is decreases. A Power quality issue is nothing but distortions in current, voltage and frequency that affect the end user equipment or disoperation; these are main problems of power quality so compensation for these problems by DPFC is presented in this paper. The control circuits for DPFC are designed by using line currents, series reference voltages and these are controlled by conventional Neuro-Fuzzy controllers. The results are observed by MATLAB/SIMULINK model.

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Shimoda, Y., J. Yui, Y. Zhang, A. Hatori, M. Ogawa, M. Fujinaga, T. Yamasaki, L. Xie, K. Kumata, and M. R. Zhang. "Radiosynthesis and evaluation of N-(3,4-dimethylisoxazol-5-yl)piperazine-4-[4-(4-fluorophenyl)thiazol-2-yl]-1-[11C]carboxamide for in vivo positron emission tomography imaging of fatty acid amide hydrolase in brain." RSC Advances 5, no. 128 (2015): 106122–27. http://dx.doi.org/10.1039/c5ra22500k.

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Chakravorty, J., and J. Saraswat. "Improving Power Flow Capacity of Transmission Lines Using DPFC with a PEM Fuel Cell." Engineering, Technology & Applied Science Research 9, no. 6 (December 1, 2019): 4883–85. http://dx.doi.org/10.48084/etasr.3155.

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The electrical power system is one complex architecture integrating generation, transmission, distribution, and utilization sections. The exponential increase in power requirements made this system more complex and dynamic. Providing good quality and uninterrupted power has become a challenge. In this respect, FACTS devices are playing a vital role in improving power quality and also in increasing the transmission capacity of lines. In this paper. Distributed Power Flow Controller (DPFC), with a PEM fuel cell, has been used in an IEEE-14 bus system to improve system power flow capacity. The proposed IEEE-14 bus with DPFC has been simulated in MATLAB/SIMULINK. The effects are exhibited and analyzed.

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Goud, B. Srikanth, Ch Rami Reddy, Mohit Bajaj, Ehab E. Elattar, and Salah Kamel. "Power Quality Improvement Using Distributed Power Flow Controller with BWO-Based FOPID Controller." Sustainability 13, no. 20 (October 11, 2021): 11194. http://dx.doi.org/10.3390/su132011194.

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The integration of hybrid renewable energy sources (HRESs) into the grid is currently being encouraged to meet the increasing demand for electric power and reduce fossil fuels which are causing environmental-related problems. Integration of HRESs into the grid can create some power quality (PQ) problems. To mitigate PQ problems and improve the performance of grid-connected HRESs some flexible devices should be used. This paper presents a distributed power flow controller (DPFC), as a type of flexible device to mitigate some PQ problems, including voltage sag, swell, disruptions, and eliminating the harmonics in a hybrid power system (HPS). The HPS presented in this work comprises a photo voltaic (PV) system, wind turbine (WT) and battery energy storage system (BESS). As a result, black widow optimization (BWO) with DPFC with real and reactive power (DPFC-PQ) is built in this paper to solve the PQ issues in HRES systems. The main aim of the work is to mitigate PQ problems and compensate for load demand in the HRES scheme. The controller used to drive this DPFC-PQ is a fractional-order PID (FOPID) controller optimized by the black widow optimization (BWO) technique. To assess the capability of BWO in fine-tuning the FOPID controller parameters, twelve optimization techniques were presented: P&O, PSO, Cuckoo, GA, GSA, BBO, Whale, ESA, RFA, ASO, and EVORFA. Additionally, a comparison between the FOPID controller and the classical PI controller is introduced. The results showed that the proposed BWO-FOPID controller for DFPC had mitigated the PQ problems in grid-connected HRESs. The system’s performance with the presented BWO-FOPID controller is compared with eleven optimization techniques used to optimize the FOPID controller and also compared with the conventional PI controller. The design of the proposed system is implemented in the MATLAB/Simulink platform and performances were analyzed.

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Schmaal, Lianne, Anne-Laura van Harmelen, Vasiliki Chatzi, Elizabeth T. C. Lippard, Yara J. Toenders, Lynnette A. Averill, Carolyn M. Mazure, and Hilary P. Blumberg. "Imaging suicidal thoughts and behaviors: a comprehensive review of 2 decades of neuroimaging studies." Molecular Psychiatry 25, no. 2 (December 2, 2019): 408–27. http://dx.doi.org/10.1038/s41380-019-0587-x.

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AbstractIdentifying brain alterations that contribute to suicidal thoughts and behaviors (STBs) are important to develop more targeted and effective strategies to prevent suicide. In the last decade, and especially in the last 5 years, there has been exponential growth in the number of neuroimaging studies reporting structural and functional brain circuitry correlates of STBs. Within this narrative review, we conducted a comprehensive review of neuroimaging studies of STBs published to date and summarize the progress achieved on elucidating neurobiological substrates of STBs, with a focus on converging findings across studies. We review neuroimaging evidence across differing mental disorders for structural, functional, and molecular alterations in association with STBs, which converges particularly in regions of brain systems that subserve emotion and impulse regulation including the ventral prefrontal cortex (VPFC) and dorsal PFC (DPFC), insula and their mesial temporal, striatal and posterior connection sites, as well as in the connections between these brain areas. The reviewed literature suggests that impairments in medial and lateral VPFC regions and their connections may be important in the excessive negative and blunted positive internal states that can stimulate suicidal ideation, and that impairments in a DPFC and inferior frontal gyrus (IFG) system may be important in suicide attempt behaviors. A combination of VPFC and DPFC system disturbances may lead to very high risk circumstances in which suicidal ideation is converted to lethal actions via decreased top-down inhibition of behavior and/or maladaptive, inflexible decision-making and planning. The dorsal anterior cingulate cortex and insula may play important roles in switching between these VPFC and DPFC systems, which may contribute to the transition from suicide thoughts to behaviors. Future neuroimaging research of larger sample sizes, including global efforts, longitudinal designs, and careful consideration of developmental stages, and sex and gender, will facilitate more effectively targeted preventions and interventions to reduce loss of life to suicide.

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Meyers, P. M. "Commentary on 'Results of epistaxis embosurgery using DPFC'." Journal of NeuroInterventional Surgery 2, no. 2 (May 27, 2010): 176. http://dx.doi.org/10.1136/jnis.2010.002204.

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Yuan, Zhihui, Sjoerd W. H. de Haan, Jan Braham Ferreira, and Dalibor Cvoric. "A FACTS Device: Distributed Power-Flow Controller (DPFC)." IEEE Transactions on Power Electronics 25, no. 10 (October 2010): 2564–72. http://dx.doi.org/10.1109/tpel.2010.2050494.

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Xiao, Mengmeng, and Shaorong Wang. "Coordination Control Method Suitable for Practical Engineering Applications for Distributed Power Flow Controller (DPFC)." Energies 11, no. 12 (December 4, 2018): 3406. http://dx.doi.org/10.3390/en11123406.

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To control multiple series units of distributed power flow controller (DPFC), a hierarchical control method is proposed. This coordination control system consists of a coordination controller and multiple series unit controllers. According to the demand of power flow ordered by a dispatch center, the corresponding series-compensated voltage is calculated by a high-level controller and transferred to each series unit controller. Comparing the targeted compensated voltage with actual injected voltage, the modulation signal of the converter will be modified to change the power flow accurately. The DPFC system model is built in Power Systems Computer Aided Design/ Electromagnetic Transients including DC (PSCAD/EMTDC). The simulation result indicates that the proposed hierarchical control method is effective and can be considered as an option for practical engineering applications in the future.

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Narasimha Rao, D., and V. Saritha. "Power System Oscillation Damping Using New Facts Device." International Journal of Electrical and Computer Engineering (IJECE) 5, no. 2 (April 1, 2015): 198. http://dx.doi.org/10.11591/ijece.v5i2.pp198-204.

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This paper presents about improving stability of the system which can be possible with new FACTS device with more convenient. FACTS devices come under the influence of power electronics equipment. Distributed Power Flow Controller is a FACTS device used for damping low frequency oscillation with new controlling approach. It is valid for a wide range of the operating condition. In this work explain the basic model and its steady state operation, mathematical analysis injection of current control model of the DPFC. Using damping controller used in DPFC facts device as input to implement the task of power oscillation damping .Here this work had a brief study on damping, terminal voltage and excitation voltage at different load conditions, simulation results demonstrate damping low frequency oscillation at nominal, light and heavy loading conditions

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Rao, Srinivas G., Graham V. Williams, and Patricia S. Goldman-Rakic. "Isodirectional Tuning of Adjacent Interneurons and Pyramidal Cells During Working Memory: Evidence for Microcolumnar Organization in PFC." Journal of Neurophysiology 81, no. 4 (April 1, 1999): 1903–16. http://dx.doi.org/10.1152/jn.1999.81.4.1903.

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Isodirectional tuning of adjacent interneurons and pyramidal cells during working memory: evidence for microcolumnar organization in PFC. Studies on the cellular mechanisms of working memory demonstrated that neurons in dorsolateral prefrontal cortex (dPFC) exhibit directionally tuned activity during an oculomotor delayed response. To determine the particular contributions of pyramidal cells and interneurons to spatial tuning in dPFC, we examined both individually and in pairs the tuning properties of regular-spiking (RS) and fast-spiking (FS) units that represent putative pyramidal cells and interneurons, respectively. Our main finding is that FS units possess spatially tuned sensory, motor, and delay activity (i.e., “memory fields”) similar to those found in RS units. Furthermore, when recorded simultaneously at the same site, the majority of neighboring neurons, whether FS or RS, displayed isodirectional tuning, i.e., they shared very similar tuning angles for the sensory and delay phases of the task. As the trial entered the response phase of the task, many FS units shifted their direction of tuning and became cross-directional to adjacent RS units by the end of the trial. These results establish that a large part of inhibition in prefrontal cortex is spatially oriented rather than being untuned and simply regulating the threshold response of pyramidal cell output. Moreover, the isodirectional tuning between adjacent neurons supports a functional microcolumnar organization in dPFC for spatial memory fields similar to that found in other areas of cortex for sensory receptive fields.

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Naveena Bhargavi, R. "Design and Control of Distributed Power-Flow Controller (DPFC)." CVR Journal of Science & Technology 03, no. 1 (December 1, 2012): 44–48. http://dx.doi.org/10.32377/cvrjst0310.

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Li, Jin, Ya Min Pi, and Hui Yuan Yang. "Study on Improving Power System Damping by Using DPFC." Advanced Materials Research 986-987 (July 2014): 1286–90. http://dx.doi.org/10.4028/www.scientific.net/amr.986-987.1286.

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In this paper, the series converters of Distributed Power Flow Controller are the main object of study. Its mechanism of suppressing power system oscillations is studied by theoretical analysis and formula derivation, which relies on a single-machine infinite-bus power system, installed the series converters. Then based on the mechanism, adopting the classic PI control and the damping controller, designed the transient stability control loop for the series converters. Finally, simulations performed by PSCAD/EMTDC, the results show that DPFC device can effectively suppress oscillation and improve system stability.

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Akram, Zeba. "Improvement in Power Quality in Power system Through of DPFC." International Journal of Trend in Scientific Research and Development Volume-2, Issue-4 (June 30, 2018): 55–62. http://dx.doi.org/10.31142/ijtsrd12959.

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Anand, Vikash, and S. K. Mallik. "Introducing Supplementary Control Scheme to DPFC During Series Converter Failure." Journal of Engineering and Applied Sciences 14, no. 7 (December 31, 2019): 2124–34. http://dx.doi.org/10.36478/jeasci.2019.2124.2134.

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Muri, R. M., A. I. Vermersch, S. Rivaud, B. Gaymard, and C. Pierrot-Deseilligny. "Effects of single-pulse transcranial magnetic stimulation over the prefrontal and posterior parietal cortices during memory-guided saccades in humans." Journal of Neurophysiology 76, no. 3 (September 1, 1996): 2102–6. http://dx.doi.org/10.1152/jn.1996.76.3.2102.

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1. We used single-pulse transcranial magnetic stimulation (TMS) to explore the temporal organization of the cortical control of memory-guided saccades in eight humans. The posterior parietal cortex (PPC) or the dorsolateral prefrontal cortex (DPFC), which are both known to be involved in the control of such saccades, were stimulated on the right side at different time intervals after the presentation of a flashed lateral visual target. The memorization delay was 2,000 ms. Single pulses were applied at 160, 260, and 360 ms after the flashed target, during the period of 700 and 1,500 ms, and finally at 2,100 ms, i.e., 100 ms after the extinguishing of the central fixation point. The effects of TMS were evaluated by calculating the percentage of error in amplitude (PEA) and latency of memory-guided saccades. The PEA was determined for the primary saccade (motor aspect) and the final eye position, i.e., after the end saccade (mnemonic aspect). Stimulation over the occipital cortex at the same time intervals served as control experiments. 2. After PPC stimulation, a significant increase in the PEA of the primary saccade and final eye position existed for contralateral saccades, compared with the PEA without stimulation, when stimulation was applied 260 ms after target presentation, but not at other time intervals. There was no significant effect on ipsilateral saccades. Latency was significantly increased bilaterally when stimulation was performed 2,100 ms after target presentation. 3. After prefrontal stimulation, a significant increase in the PEA of the primary saccade and final eye position existed for contralateral saccades, when stimulation was applied between 700 and 1,500 ms after target presentation, but not at other time intervals. There was no significant effect on ipsilateral saccades. Latency was not affected by prefrontal TMS at any stimulation times. 4. Occipital stimulation resulted in no significant effect on the PEA and latency of ipsilateral or contralateral saccades, in particular including the application at 260 ms after target presentation or during the memorization phase. 5. From these results it may be concluded that the observed effects of TMS on saccade accuracy were specific to the stimulated region and specific to the stimulation time. The PPC seems to be involved in the preparation of saccade amplitude, during the early phase of the paradigm, i.e., the sensorimotor processing period, whereas the DPFC could play a role during the later phase of the paradigm, i.e., the memorization period. Therefore in humans these results support the experimental findings suggesting that sensorimotor integration is controlled by the PPC and spatial memory by the DPFC. Furthermore, our results suggest that the PPC, although not the DPFC, plays a role in saccade triggering.

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Cao(Cao), Xinwei, Youjun Zhang(Zhang), and Zhengzheng Sun(Sun). "Muti-level voltage synthetic voltage direct power flow controller." Journal of Physics: Conference Series 2108, no. 1 (November 1, 2021): 012081. http://dx.doi.org/10.1088/1742-6596/2108/1/012081.

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Abstract Aiming at the defects of DC energy storage elements, complex structure and large volume of unified power flow controller (UPFC), the paper combines flying capacitor multilevel technology and voltage vector synthesis technology with unified direct power flow controller. A three-level direct power flow controller (3L-DPFC) and a new control strategy are proposed. By obtaining the power parameters of the receiving end and substituting them into the derived calculation formula, the compensation voltage can be deduced to adjust the phase and amplitude, and the change relationship between the compensation voltage and the power parameters of the receiving end can be calculated through multiple groups of data, so as to adjust the active power flow and reactive power flow in the power grid. Compared with the unified direct power flow controller, it has the advantages of no DC energy storage element, small volume, simple structure, and the voltage stress of each switch is reduced by half, which reduces the failure rate and economic cost of the controller. In the paper, the topology and control strategy of three-level synthetic DPFC are described in detail, and its buck AC conversion theoretical analysis is verified by simulation.

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Khakdaman, Hamidreza, Yves Bourgault, and Marten Ternan. "A Mathematical Model of a Direct Propane Fuel Cell." Journal of Chemistry 2015 (2015): 1–13. http://dx.doi.org/10.1155/2015/102313.

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A rigorous mathematical model for direct propane fuel cells (DPFCs) was developed. Compared to previous models, it provides better values for the current density and the propane concentration at the exit from the anode. This is the first DPFC model to correctly account for proton transport based on the combination of the chemical potential gradient and the electrical potential gradient. The force per unit charge from the chemical potential gradient (concentration gradient) that pushes protons from the anode to the cathode is greater than that from the electrical potential gradient that pushes them in the opposite direction. By including the chemical potential gradient, we learn that the proton concentration gradient is really much different than that predicted using the previous models that neglected the chemical potential gradient. Also inclusion of the chemical potential gradient made this model the first one having an overpotential gradient (calculated from the electrical potential gradient) with the correct slope. That is important because the overpotential is exponentially related to the reaction rate (current density). The model described here provides a relationship between the conditions inside the fuel cell (proton concentration, overpotential) and its performance as measured externally by current density and propane concentration.

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B, Srikanth Goud. "BWO Strategy for Power Quality Improvement in HRES Grid-Connected DPFC System." Smart Science 9, no. 3 (May 5, 2021): 226–43. http://dx.doi.org/10.1080/23080477.2021.1920142.

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Sahithi, M. Bindu, and Y. Vishnu Murthulu. "Power Quality Enhancement and Mitigation of Voltage Sag and Swell using DPFC." International Journal of Engineering Trends and Technology 40, no. 5 (October 25, 2016): 265–71. http://dx.doi.org/10.14445/22315381/ijett-v40p243.

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Chen, Qian, Chengyu Lu, Jingen Song, Hua Xu, Wulue Pan, and Peng Qiu. "Design and application of short circuit test scheme for Hu Zhou DPFC project." Energy Reports 8 (November 2022): 363–69. http://dx.doi.org/10.1016/j.egyr.2022.08.080.

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AKHIB KHAN, BAHAMANI, G. M. SREERAMA REDDY, and GANESH V. "Digital Simulation of Eight Bus System with DPFC by Employing Five Level Inverter." i-manager's Journal on Power Systems Engineering 4, no. 3 (2016): 1. http://dx.doi.org/10.26634/jps.4.3.8267.

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Srinivasarao, Budi, G. Sreenivasan, and Swathi Sharma. "MITIGATION OF VOLTAGE DISTRUBANCES IN SMIB SYSTEM USING ANN/FUZZY BASED DPFC SYSTEM." International Journal of Advanced Research 5, no. 4 (April 30, 2017): 1571–78. http://dx.doi.org/10.21474/ijar01/3982.

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Cullell, Natalia, Cristina Gallego-Fábrega, Jara Cárcel-Márquez, Elena Muiño, Laia Llucià-Carol, Miquel Lledós, Jesús M. Martín-Campos, et al. "ICA1L Is Associated with Small Vessel Disease: A Proteome-Wide Association Study in Small Vessel Stroke and Intracerebral Haemorrhage." International Journal of Molecular Sciences 23, no. 6 (March 15, 2022): 3161. http://dx.doi.org/10.3390/ijms23063161.

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Small vessel strokes (SVS) and intracerebral haemorrhages (ICH) are acute outcomes of cerebral small vessel disease (SVD). Genetic studies combining both phenotypes have identified three loci associated with both traits. However, the genetic cis-regulation at the protein level associated with SVD has not been studied before. We performed a proteome-wide association study (PWAS) using FUSION to integrate a genome-wide association study (GWAS) and brain proteomic data to discover the common mechanisms regulating both SVS and ICH. Dorsolateral prefrontal cortex (dPFC) brain proteomes from the ROS/MAP study (N = 376 subjects and 1443 proteins) and the summary statistics for the SVS GWAS from the MEGASTROKE study (N = 237,511) and multi-trait analysis of GWAS (MTAG)-ICH–SVS from Chung et al. (N = 240,269) were selected. We performed PWAS and then a co-localization analysis with COLOC. The significant and nominal results were validated using a replication dPFC proteome (N = 152). The replicated results (q-value < 0.05) were further investigated for the causality relationship using summary data-based Mendelian randomization (SMR). One protein (ICA1L) was significantly associated with SVS (z-score = −4.42 and p-value = 9.6 × 10−6) and non-lobar ICH (z-score = −4.8 and p-value = 1.58 × 10−6) in the discovery PWAS, with a high co-localization posterior probability of 4. In the validation PWAS, ICA1L remained significantly associated with both traits. The SMR results for ICA1L indicated a causal association of protein expression levels in the brain with SVS (p-value = 3.66 × 10−5) and non-lobar ICH (p-value = 1.81 × 10−5). Our results show that the association of ICA1L with SVS and non-lobar ICH is conditioned by the cis-regulation of its protein levels in the brain.

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Ahmed, Shaheen, and Sven Vanneste. "132 The Underlying Effect of Burst Stimulation on Chronic Pain Using Multimodal Neuroimaging - EEG, fMRI and PET." Neurosurgery 64, CN_suppl_1 (August 24, 2017): 230. http://dx.doi.org/10.1093/neuros/nyx417.132.

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Abstract INTRODUCTION Minimally invasive neuromodulation such as spinal cord stimulation (SCS) and occipital nerve stimulation (ONS) have shown to be successful for treatment of different types of pain such as chronic back or leg pain, complex regional pain syndrome (CRPS), and fibromyalgia. Recently, novel stimulation paradigm called burst stimulation was developed that suppresses pain to better extent than classical tonic stimulation. From clinical point of view, burst stimulation is very promising; however, little is known about its underlying mechanism. Hence, in this work we investigate mechanism of action for burst stimulation in different patient groups and controls using different neuroimaging multimodalities such as EEG, fMRI and PET. METHODS Control subjects and patients with chronic back or leg pain, CRPS, or fibromyalgia enrolled for study. Both controls and patients received SCS or ONS and sham, tonic, and burst stimulation in fMRI, PET, and EEG. RESULTS >EEG shows significant changes for burst stimulation compared to tonic and sham stimulation; evident by increased activity at dorsal anterior cingulate cortex (dACC), dorsolateral prefrontal cortex (dPFC), primary somatosensory cortex, and posterior cingulate cortex (PSC) in alpha frequency band. PET further confirmed by showing increased tracer capitation for burst in dACC, pregenual anterior cingulate cortex (pgACC), parahippocampus, and fusiform gyrus. Furthermore, fMRI showed burst changes in dACC, dPFC, pgACC, cerebellum, hypothalamus, and premotor cortex. A conjunction analysis between tonic and burst stimulation demonstrated theta activity is commonly modulated in somatosensory cortex and PSC. CONCLUSION Our data suggest that burst and tonic stimulation modulate ascending lateral and descending pain inhibitory pathways. Burst stimulation adds by modulating the medial pain pathway, possibly by direct modulation of spinothalamic pathway, as suggested by animal research. Burst normalizes an imbalance between ascending pain via medial system and descending pain inhibitory activity, which could be a plausible reason it's better than to tonic stimulation.

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Venkatesh, R., M. Rekha, and G. Sundar. "Deciding optimal location for placing FACTS devices [UPFC, IPQC, DPFC] using Bang-Bang control technique." IOSR Journal of Electrical and Electronics Engineering 9, no. 1 (2014): 35–46. http://dx.doi.org/10.9790/1676-09123546.

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Yuruk, Deniz, Can Ozger, Juan F. Garzon, Jarrod M. Leffler, Julia Shekunov, Jennifer L. Vande Voort, Michael J. Zaccariello, Paul A. Nakonezny, and Paul E. Croarkin. "Sequential bilateral accelerated theta burst stimulation in adolescents with suicidal ideation associated with major depressive disorder: Protocol for a randomized controlled trial." PLOS ONE 18, no. 4 (April 13, 2023): e0280010. http://dx.doi.org/10.1371/journal.pone.0280010.

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Background Suicide is a leading cause of death in adolescents worldwide. Previous research findings suggest that suicidal adolescents with depression have pathophysiological dorsolateral prefrontal cortex (DLPFC) deficits in γ-aminobutyric acid neurotransmission. Interventions with transcranial magnetic stimulation (TMS) directly address these underlying pathophysiological deficits in the prefrontal cortex. Theta burst stimulation (TBS) is newer dosing approach for TMS. Accelerated TBS (aTBS) involves administering multiple sessions of TMS daily as this dosing may be more efficient, tolerable, and rapid acting than standard TMS. Materials and methods This is a randomized, double-blind, sham-controlled trial of sequential bilateral aTBS in adolescents with major depressive disorder (MDD) and suicidal ideation. Three sessions are administered daily for 10 days. During each session, continuous TBS is administered first to the right DPFC, in which 1,800 pulses are delivered continuously over 120 seconds. Then intermittent TBS is applied to the left DPFC, in which 1,800 pulses are delivered in 2-second bursts and repeated every 10 seconds for 570 seconds. The TBS parameters were adopted from prior research, with 3-pulse, 50-Hz bursts given every 200 ms (at 5 Hz) with an intensity of 80% active motor threshold. The comparison group will receive 3 daily sessions of bilateral sham TBS treatment for 10 days. All participants will receive the standard of care for patients with depression and suicidal ideation including daily psychotherapeutic skill sessions. Long-interval intracortical inhibition (LICI) biomarkers will be measured before and after treatment. Exploratory measures will be collected with TMS and electroencephalography for biomarker development. Discussion This is the first known randomized controlled trial to examine the efficacy of sequential bilateral aTBS for treating suicidal ideation in adolescents with MDD. Results from this study will also provide opportunities to further understand the neurophysiological and molecular mechanisms of suicidal ideation in adolescents. Trial registration Investigational device exemption (IDE) Number: G200220, ClinicalTrials.gov (ID: NCT04701840). Registered August 6, 2020. https://clinicaltrials.gov/ct2/show/NCT04502758?term=NCT04701840&draw=2&rank=1.

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Reddy, D. Raja, and Dr B. Venkata Prasanth. "Comarision Of Distributed Power-Flow Controller (DPFC) And Generalized Unified Power Flow Controller (GUPFC) In Power Quality Improvement." IJIREEICE 3, no. 4 (April 15, 2015): 104–8. http://dx.doi.org/10.17148/ijireeice.2015.3423.

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Pavan Kumar Naidu, R., and S. Meikandasivam. "Power quality enhancement in a grid-connected hybrid system with coordinated PQ theory & fractional order PID controller in DPFC." Sustainable Energy, Grids and Networks 21 (March 2020): 100317. http://dx.doi.org/10.1016/j.segan.2020.100317.

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Han, Zhilu, Guangzhu Wang, Yuhui Liu, and Wenjie Guo. "High Step-Up Resonant DC–DC Converter With Resonant Network for Electrical Collection Systems." Journal of Physics: Conference Series 2260, no. 1 (April 1, 2022): 012012. http://dx.doi.org/10.1088/1742-6596/2260/1/012012.

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Abstract The efficiency of renewable energy electrical collection can be effectively improved by adopting the high voltage direct current (HVDC) electrical collection method. The low-voltage DC power is stepped up to the high-voltage level for HVDC transmission by one-stage step-up type, which can reduce the cost of high-voltage large-capacity DC-DC converters. However, the high cost of DC-DC converters which can achieve high step-up ratio, such as modular multilevel converter (MMC), limits the development of the one-stage step-up type. In this paper, a low-cost DC-DC converter with high step-up ratio which can realize the bidirectional flow of energy is proposed. The total step-up ratio is the product of high-frequency transformer ratio, resonant network gain and step-up ratio of voltage doubler rectifier circuit. Meanwhile, the direct power factor control (DPFC) strategy is proposed based on the idea of controlling active power to achieve the goal of controlling output voltage. Finally, the step-up ratio of the DC-DC converter can reach 160 times, and realize zero-voltage switching (ZVS) turn-on of the switches and zero-current switching (ZCS) turn-off of the diodes.

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Mota, Jaqueline Montoril Sampaio, Gustavo Hermes Soares, Maria Gabriela Haye Biazevic, Mariana Gabriel, Thais Torralbo Lopez Capp, and Edgard Michel-Crosato. "Tradução e adaptação transcultural da versão brasileira do questionário Dental Patient Feedback on Consultation." Research, Society and Development 10, no. 7 (June 23, 2021): e33710716694. http://dx.doi.org/10.33448/rsd-v10i7.16694.

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Este estudo teve como proposição realizar a tradução e a adaptação transcultural do questionário Dental Patient Feedback on Consultation (DPFC) para o português e no contexto cultural brasileiro. Para o processo de tradução e adaptação, foram seguidas diretrizes internacionais propostas na literatura estruturadas em cinco fases: autorização dos autores do questionário, tradução do questionário para o Português brasileiro por dois profissionais independentes, concordância entre as duas versões da tradução, retrotradução para o inglês e avaliação pelo comitê de especialistas. A versão preliminar do questionário foi respondida por usuários de Unidades Básicas de Saúde localizadas em Belém, Pará, a fim de avaliar a compreensão dos itens do questionário. As duas traduções iniciais não apresentaram discrepâncias significativas, o que facilitou a síntese em uma única versão. O comitê de especialistas revisou todas as traduções e chegou a um consenso sobre a versão preliminar do questionário. A partir das respostas dos participantes do estudo a respeito da compreensão do questionário, foram feitas alterações nos itens 5 e 7. A compreensão dos itens do questionário pelos participantes aumentou substancialmente após as modificações. A versão brasileira do questionário Dental Patient Feedback on Consultation demonstrou equivalência com os significados do instrumento original. O questionário teve boa aceitação e boa compreensão pelos participantes, o que demonstrou a sua adequação para o uso na população brasileira.

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Baeken, C., R. De Raedt, N. Vanderbruggen, D. Zeeuws, L. Santermans, C. Van Hove, and A. Bossuyt. "The influence of treatment-resistance on the serotonin 2A receptor in unipolar melancholic depression." European Psychiatry 26, S2 (March 2011): 602. http://dx.doi.org/10.1016/s0924-9338(11)72309-4.

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IntroductionMajor depression is one of the most common mental diseases, and quite a number of patients are resistant to several psychopharmacological interventions, even when applying current treatment guidelines. To date, it remains unclear as to how the serotonergic system is implicated in treatment-resistance found in melancholically depressed patients.Objectives & aimsIn this study, we examined the involvement of post-synaptic 5-HT2A receptors in the pathophysiology of treatment resistance in major depression with 123I-5-I-R91150 SPECT, focusing on the frontal cortex and hippocampus.Method15 unipolar antidepressant naïve (ADN) patients and 15 treatment-resistant depressed (TRD) patients, all of the melancholic subtype, matched for age and gender were studied. All subjects were antidepressant free when they underwent a static 123I-5-I-R91150 SPECT scan.ResultsCompared to ADN patients, TRD patients displayed significantly less 5-HT2A receptor binding index (BI) in the dorsal regions of the prefrontal cortex and in the anterior cingulate cortex. No hippocampal 5-HT2A receptor BI differences were observed.ConclusionsOur results suggest that when confronted with treatment resistance in melancholic depression the 5-HT2A receptors in the DPFC-ACC axis are significantly more down-regulated when compared to depressed ADN patients. This might to some extent explain the observed continued cognitive problems and might reflect the long-term serotonin depletion with reduced neurogenesis in treatment resistant patients.

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Sandra, Ferry, Janti Sudiono, Ciptadhi Tri Oka Binartha, Angliana Chouw, and Melanie Sadono Djamil. "Growth and Osteogenic Differentiation of CD117+ Dental Pulp and Periodontal Ligament Cells." Indonesian Biomedical Journal 9, no. 2 (August 1, 2017): 78. http://dx.doi.org/10.18585/inabj.v9i2.286.

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BACKGROUND: Dental pulp stem cell (DPSC) and periodontal ligament stem cell (PDLSC) have been suggested as valuable seed cells for bone engineering, suggesting that both stem cells are potential osteogenic sources. Since DPSC and PDLSC seem like to have similar potential in bone formation, we conducted a study to compare morphology, immunophenotype and cell growth of DPSC and PDLSC isolated from the same teeth.METHODS: Human dental pulps and periodontal ligaments were obtained from freshly extracted partial impacted third molar teeth. Collected samples were digested with type I collagenase. Resulted cell suspension was washed and cultured. For biomarker identification, the cells were fixed and bound with anti-fluorescein isothiocyanate (FITC)-cluster of differentiation (CD)117 antibody. For cell growth quantification, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used. Meanwhile for osteogenic differentiation, the cells were cultured in osteogenic medium for 1-3 weeks, fixed and stained with alizarin red.RESULTS: Morphology of dental pulps cell (DPC) and periodontal ligament cell (PDLC) in passage 5 was similar. Clear CD117 green fluorescence of DPC and PDLC in passage 5 was observed. Cell growth rate of PDLC was higher than the one of DPC, 0.3858 and 0.3848 respectively. DPC formed bone nodule on the third week culture in osteogenic medium, while PDLC showed bone nodule formation on the second week culture.CONCLUSION: We suggest that DPC and PDLC are potential seed cells for osteogenic regeneration, since they had cell growth capacity and osteogenic differentiation, particularly PDLC that had faster osteogenic differentiation.KEYWORDS: dental pulp, periodontal ligament, cell, growth, osteogenic differentiation

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Ishizaka, Aya, Taketoshi Mizutani, Kazuyoshi Kobayashi, Toshio Tando, Kouhei Sakurai, Toshinobu Fujiwara, and Hideo Iba. "Double Plant Homeodomain (PHD) Finger Proteins DPF3a and -3b Are Required as Transcriptional Co-activators in SWI/SNF Complex-dependent Activation of NF-κB RelA/p50 Heterodimer." Journal of Biological Chemistry 287, no. 15 (February 13, 2012): 11924–33. http://dx.doi.org/10.1074/jbc.m111.322792.

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We have previously shown that DPF2 (requiem/REQ) functions as a linker protein between the SWI/SNF complex and RelB/p52 NF-κB heterodimer and plays important roles in NF-κB transactivation via its noncanonical pathway. Using sensitive 293FT reporter cell clones that had integrated a SWI/SNF-dependent NF-κB reporter gene, we find in this study that the overexpression of DPF1, DPF2, DPF3a, DPF3b, and PHF10 significantly potentiates the transactivating activity of typical NF-κB dimers. Knockdown analysis using 293FT reporter cells that endogenously express these five proteins at low levels clearly showed that DPF3a and DPF3b, which are produced from the DPF3 gene by alternative splicing, are the most critical for the RelA/p50 NF-κB heterodimer transactivation induced by TNF-α stimulation. Our data further show that this transactivation requires the SWI/SNF complex. DPF3a and DPF3b are additionally shown to interact directly with RelA, p50, and several subunits of the SWI/SNF complex in vitro and to be co-immunoprecipitated with RelA/p50 and the SWI/SNF complex from the nuclear fractions of cells treated with TNF-α. In ChIP experiments, we further found that endogenous DPF3a/b and the SWI/SNF complex are continuously present on HIV-1 LTR, whereas the kinetics of RelA/p50 recruitment after TNF-α treatment correlate well with the viral transcriptional activation levels. Additionally, re-ChIP experiments showed DPF3a/b and the SWI/SNF complex associate with RelA on the endogenous IL-6 promoter after TNF-α treatment. In conclusion, our present data indicate that by linking RelA/p50 to the SWI/SNF complex, DPF3a/b induces the transactivation of NF-κB target gene promoters in relatively inactive chromatin contexts.

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Shunaev, Vladislav V., and Olga E. Glukhova. "Nanoindentation of Graphene/Phospholipid Nanocomposite: A Molecular Dynamics Study." Molecules 26, no. 2 (January 11, 2021): 346. http://dx.doi.org/10.3390/molecules26020346.

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Graphene and phospholipids are widely used in biosensing and drug delivery. This paper studies the mechanical and electronic properties of a composite based on two graphene flakes and dipalmitoylphosphatidylcholine (DPPC) phospholipid molecules located between them via combination of various mathematical modeling methods. Molecular dynamics simulation showed that an adhesion between bilayer graphene and DPCC increases during nanoindentation of the composite by a carbon nanotube (CNT). Herewith, the DPPC molecule located under a nanotip takes the form of graphene and is not destroyed. By the Mulliken procedure, it was shown that the phospholipid molecules act as a “buffer” of charge between two graphene sheets and CNT. The highest values of electron transfer in the graphene/DPPC system were observed at the lower indentation point, when the deflection reached its maximum value.

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Shunaev, Vladislav V., and Olga E. Glukhova. "Nanoindentation of Graphene/Phospholipid Nanocomposite: A Molecular Dynamics Study." Molecules 26, no. 2 (January 11, 2021): 346. http://dx.doi.org/10.3390/molecules26020346.

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Graphene and phospholipids are widely used in biosensing and drug delivery. This paper studies the mechanical and electronic properties of a composite based on two graphene flakes and dipalmitoylphosphatidylcholine (DPPC) phospholipid molecules located between them via combination of various mathematical modeling methods. Molecular dynamics simulation showed that an adhesion between bilayer graphene and DPCC increases during nanoindentation of the composite by a carbon nanotube (CNT). Herewith, the DPPC molecule located under a nanotip takes the form of graphene and is not destroyed. By the Mulliken procedure, it was shown that the phospholipid molecules act as a “buffer” of charge between two graphene sheets and CNT. The highest values of electron transfer in the graphene/DPPC system were observed at the lower indentation point, when the deflection reached its maximum value.

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Journal articles on the topic 'DPFC'

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