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In vivo antianxiety and antidepressant activity of Murraya paniculata leaf extracts

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Journal of Integrative Medicine 2017年第4期15卷 320-325页

作者： Pragya Sharma Sonali Batra ashwani kumar Anupam Sharma University Institute of Pharmaceutical Sciences Panjab University

OBJECTIVE： Different parts of Murraya paniculata have been used traditionally for treating several ailments including mental disorders. The present study was designed to evaluate the antianxiety and antidepressant potential of M. paniculata leaves using elevated plus maze model and forced swim test, respectively. METHODS： Extracts of M. panicu/ata made with petroleum ether （60-80 ℃）, chloroform, ethanol and water were evaluated for antianxiety and antidepressant activity. The anxiolytic chloroform extract was subjected to column chromatography, yielding five fractions （F1-F5）. Fraction F5 （100 mg/kg）, which showed notable anxiolytic activity, was further chromatographed to get four subfractions （F5.1-F5.4）. Simultaneously, the ethano extract was partitioned with ethyl acetate to obtain ethyl acetate soluble fraction （EASF） and ethyl acetate insoluble fraction. Phytochemical screening of bioactive extracts/fractions and detection of mahanimbine in M paniculata leaf extract by thin-layer chromatography was also carried out. RESULTS： Fraction F5.3 （25 mg/kg） and EASF （20 mg/kg） showed significant anxiolytic and antidepressant activity, respectively. Thin-layer chromatography and phytochemical screening demonstrated the absence of mahanimbine in M. paniculata leaves. Coumarins were observed to be responsible for the anxiolytic activity. CONCLUSION： The results validate the traditional use of M. paniculata leaves in the treatment of menta disorders.

关键词： Murraya paniculata anxiety depressant coumarins mahanimbine plants, medicinal

Optimization of Distributed Solar Photovoltaic Power Generation in Day-ahead Electricity Market Incorporating Irradiance Uncertainty

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 545-560页

作者： Anu Singla Kanwardeep Singh Vinod kumar yadav the Department of Electrical Engineering Chitkara University Institute of Engineering and TechnologyChitkara UniversityPunjabIndia the Department of Electrical Engineering Guru Nanak Dev Engineering CollegeLudhianaIndia(affiliated to I.K.Gujral Punjab Technical UniversityKapurthalaIndia) the Department of Electrical Engineering Delhi Technological UniversityDelhiIndia

This paper proposes a simple and practical approach to model the uncertainty of solar irradiance and determines the optimized day-ahead(DA)schedule of electricity *** problem formulation incorporates the power output of distributed solar photovoltaic generator(DSPVG)and forecasted load demands with a specified level of *** proposed approach determines the certainty levels of the random variables(solar irradiance and forecasted load demand)from their probability density function *** this process of optimization,the energy storage system(ESS)has also been mod-eled based on the fact that the energy stored during low locational marginal price(LMP)periods and dispatched during high LMP periods would strengthen the economy of DA *** objective of the formulated non-linear optimization problem is to maximize the social welfare of market participants,which incorporates the assured generation outputs of DSPVG,subject to real and reactive power balance and transmission capability constraints of the system and charging/dis-charging and energy storage constraints of *** simulation has been performed on the Indian utility 62-bus *** results are presented with a large number of cases to demonstrate the effectiveness of the proposed approach for the efficient,economic and reliable operation of DA electricity markets.

关键词： Electricity market energy storage market dispatching renewable energy social welfare solar photovoltaic power generator

Dynamic contribution of variable-speed wind energy conversion system in system frequency regulation

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Frontiers in Energy 2012年第2期6卷 184-192页

作者： Yajvender Pal VERMA ashwani kumar Department of Electrical&Electronics Engineering UIETPanjab UniversityChandigarh 160014India Department of Electrical Engineering National Institute of TechnologyKurukshetraHaryana 132119India

Frequency regulation in a generation mix having large wind power penetration is a critical issue, as wind units isolate from the grid during disturbances with advanced power electronics controllers and reduce equivalent system inertia. Thus, it is important that wind turbines also contribute to system frequency control. This paper examines the dynamic contribution of doubly fed induction generator （DFIG）-based wind turbine in system frequency regulation. The modified inertial support scheme is proposed which helps the DFIG to provide the short term transient active power support to the grid during transients and arrests the fall in frequency. The frequency deviation is considered by the controller to provide the inertial control. An additional reference power output is used which helps the DFIG to release kinetic energy stored in rotating masses of the turbine. The optimal speed control parameters have been used for the DFIG to increases its participation in frequency control. The simulations carried out in a two-area interconnected power system demonstrate the contribution of the DFIG in load frequency control.

关键词： doubly fed induction generator (DFIG) load frequency control inertial control wind energy conversion system (WECS)

Recent advances in catalytic combustion of AP-based composite solid propellants

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Defence Technology（防务技术） 2021年第3期17卷 1013-1031页

作者： Narendra yadav Prem kumar Srivastava Mohan Varma Department of Space Engineering&Rocketry India Department of Chemistry Birla Institute of TechnologyMesraRanchiIndia

Composite solid propellants(CSPs) have widely been used as main energy source for propelling the rockets in both space and military applications. Internal ballistic parameters of rockets like characteristic exhaust velocity, specific impulse, thrust, burning rate etc., are measured to assess and control the performance of rocket motors. The burn rate of solid propellants has been considered as most vital parameter for design of solid rocket motors to meet specific mission requirements. The burning rate of solid propellants can be tailored by using different constituents, extent of oxidizer loading and its particle size and more commonly by incorporating suitable combustion catalysts. Various metal oxides(MOs),complexes, metal powders and metal alloys have shown positive catalytic behaviour during the combustion of CSPs. These are usually solid-state catalysts that play multiple roles in combustion of CSPs such as reduction in activation energy, enhancement of rate of reaction, modification of sequences in reaction-phase, influence on condensed-phase combustion and participation in combustion process in gas-phase reactions. The application of nanoscale catalysts in CSPs has increased considerably in recent past due to their superior catalytic properties as compared to their bulk-sized counterparts. A large surface-to-volume ratio and quantum size effect of nanocatalysts are considered to be plausible reasons for improving the combustion characteristics of propellants. Several efforts have been made to produce nanoscale combustion catalysts for advanced propellant formulations to improve their energetics. The work done so far is largely scattered. In this review, an effort has been made to introduce various combustion catalysts having at least a metallic entity. Recent developments of nanoscale combustion catalysts with their specific merits are discussed. The combustion chemistry of a typical CSP is briefly discussed for providing a better understanding on role of co

关键词： Composite solid propellants Burn rate modifier Metallic nano-catalysts Catalytic combustion Thermal decomposition

Synthesis, antimicrobial and anti-inflammatory activities of some novel 5-substituted imidazolone analogs

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Chinese Chemical Letters 2016年第5期27卷 707-710页

作者： ashwani kumar Dhingra Bhawna Chopra Rameshwar Dass Sanjeev kumar Mittal Guru Gobind Singh College of Pharmacy Yamuna Nagar 135001 Haryana India Department of Pharmacy IK Gujral Punjab Technical University Jalandhar 144001 Punjab India Department of Industrial Chemistry Guru Nanak Khalsa College Yamuna Nagar 135001 Haryana India IEC School of Pharmacy IEC University Baddi 173205 Himachal Pardesh India

In view of potent antimicrobial and anti-inflammatory activities exhibited by S-substituted imidazolones, a variety of novel imidazolone analogs 3a-I were synthesized by the condensation of different substituted oxazolones I with various aromatic amines 2. All the synthesized compounds were screened for in vitro activities against a panel of Gram-positive and Gram-negative bacteria and the yeast-like pathogenic fungus Candida albicans. Several analogs produced good or moderate activities particularly against the tested Gram-positive bacteria Micrococcus luteus and Gram-negative bacteria Pseudornonas aeruginosa and, Meanwhile, compounds 3b and 3c displayed marked antifungal activity against C. albicans. In addition, the in vivo anti-inflammatory activity of the synthesized compounds was determined using the carrageenin-induced paw oedema method in rats. Two of S-substituted imidazo/one derivatives, 3k and 3d show good anti-inflammatory activity. The structures of all the newly svnthesized compounds were elucidated using IR, 1H NMR and 13C NMR.

关键词： Oxazolones Imidazolones Antimicrobial activity Anti-inflammatory activity

Transmission congestion management considering multiple and optimal capacity DGs

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Journal of Modern Power Systems and Clean Energy 2017年第5期5卷 713-724页

作者： Rajagopal PEESAPATI Vinod kumar yadav Niranjan kumar Department of Electrical Engineering National Institute of Technology JamshedpurJamshedpurJharkhand 831014India Department of Electrical Engineering Gautam Buddha UniversityNoida 201334India

Transmission congestion management became a grievous issue with the increase of competitiveness in the power systems. Competitiveness arises due to restructuring of the utilities along with the penetration of auxiliary services. The present study depicts a multi objective technique for achieving the optimal capacities of distributed generators(DG) such as solar, wind and biomass in order to relieve congestion in the transmission lines. Objectives like transmission congestion, real power loss, voltages and investment costs are considered to improve the technical and economical performances of the network. Multi objective particle swarm optimization algorithm is utilized to achieve the optimal sizes of unity power factor DG *** insisted methodology is practiced on IEEE-30 and IEEE-118 bus systems to check the practical *** results of the proposed approach are compared with the genetic algorithm for both single and multi-objective cases. Results revealed that the intimated method can aid independent system operator to remove the burden from lines in the contingency conditions in an optimal manner along with the improvement in voltages and a reduction in real power losses of the network.

关键词： Transmission congestion Optimal power flow Distributed generation Particle swarm optimization

Load frequency control in deregulated power system with wind integrated system using fuzzy controller

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Frontiers in Energy 2013年第2期7卷 245-254页

作者： Yajvender Pal VERMA ashwani kumar Department of Electrical & Electronics Engineering UIET PanjabUniversity Chandigarh 160014 India Department of Electrical Engineering National Institute of TechnologyKurukshetra Haryana 132119 India

This paper presents the analysis of load frequency control （LFC） of a deregulated two-area hydro-thermal power system using fuzzy logic controller, with doubly fed induction generators （DFIGs） integrated into both the control areas. The deregulation of power sector has led to the formation of new companies for generation, transmission and distribution of power. The conventional two-area power system is modified to study the effects of the bilateral contracts of companies on the system dynamics. Deregulation creates highly competitive and distributed control environment, and the LFC becomes even more challenging when wind generators are also integrated into the system. The overall inertia of the system reduces, as the wind unit does not provide inertia and isolates from the grid during disturbances. The DFIGs integrated provide inertial support to the system through modified inertial control scheme, and arrests the initial fall in frequency after disturbance. The inertial control responds to frequency deviations, which takes out the kinetic energy of the wind turbine for improving the frequency response of the system. To enhance the participation of the doubly fed induction generator （DFIG） in the frequency control, optimal values of the speed control parameters of the DFIG-based wind turbine have been obtained using integral square error （ISE） technique. The dynamics of the system have been obtained for a small load perturbation, and for contract violation using fuzzy controller.

关键词： frequency regulation fuzzy controller deregulated power system doubly fed induction generator(DFIG) bilateral contract

Continuity of cancer care in the era of COVID-19 pandemic: Role of social media in low- and middle-income countries

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World Journal of Clinical Cases 2021年第2期9卷 291-295页

作者： Sanjay kumar yadav Nishtha yadav Department of Surgery Netaji Subhash Chandra Bose Medical CollegeJabalpur 482003Madhya PradeshIndia Department of Radiology Super-specialty HospitalNetaji Subhash Chandra Bose Medical CollegeJabalpur 482003Madhya PradeshIndia

A novel coronavirus(severe acute respiratory syndrome coronavirus 2)first detected in Wuhan,China,has spread rapidly since December 2019,causing more than 1.4 million confirmed infections and 15000 fatalities(as of April 9,2020).The outbreak was declared a pandemic by the World Health Organization on March 11,***,quarantine,social distancing,and community containment measures were rapidly implemented in China,which helped in containing the ***,other low-and middle-income countries lack such extensive infrastructural capacities and *** patients are particularly at high risk of infection and mortality due to *** self-quarantine is recommended for ***,it is becoming impossible to maintain the continuity of care when cancer patients have to avoid physical *** media applications,e.g.,Facebook and WhatsApp,can provide educational group program and psychosocial support to these patients while maintain social *** have analyzed their use in this review article and how it could change the follow-up of cancer patients during this pandemic.

关键词： COVID-19 Telemedicine Cancer care Social media Low-and middleincome countries Remote monitoring

A transitioning universe with time varying G and decaying Λ

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Research in Astronomy and Astrophysics 2013年第5期13卷 501-508页

作者： Anil kumar yadav Amit Sharma Department of Physics Anand Engineering College Department of Mathematics Anand Engineering College

We present a model of a universe that transitions from an early deceleration phase to the current acceleration phase under the framework of general relativity, in the presence of gravitational coupling G（t） and cosmological terms A（t）. Einstein＇s field equations have been solved by considering the time dependent deceleration parameter （DP） which renders the scale factor e = （thekt）1/m where m, n and k are positive con- stants. The cosmological term （A （t）） is found to be positive and a decreasing function of time, which supports the result obtained from observations of type Ia supernovae. The geometrical and kinematical features of the model are examined in detail.

关键词： early universe -- large scale structure of universe