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American Journal of Plant Sciences 2016年第13期7卷 1693-1710页

作者： pallavi upadhyay Camelia Maier Department of Biology Texas Woman’s University Denton USA

Mammalian sex hormones are spread in the environment from natural and anthropogenic sources. In the present study, the effect of estradiol on Arabidopsis thaliana growth primary metabolism, phenylpropanoid and flavonoid pathways and pathogen resistance were investigated. Treatments of Arabidopsis plants with 10 and 100 nM 17β-estradiol resulted in enhanced root growth and shoot biomass. In addition, treated plants had an increased rate of photosynthesis with a concomitant increase in carbohydrate and protein accumulation. Plants exposed to higher concentrations of 17β-estradiol (10 μM) had significantly lower root growth, biomass, photosynthesis rate, primary metabolite and phenylpropanoid and flavonoid contents indicating a toxic effect of estradiol. Treatments with increasing estradiol concentrations (10 nM, 100 nM and 10 μM) resulted in the downregulation of phenylpropanoid-flavonoid pathway genes (PAL1, PAL4, CHI and ANS) and subsequent decreased accumulation of phenolics, flavonoids and anthocyanins. Estradiol-treated plants were inoculated with Pseudomonas syringae pv. Tomato DC3000 and basal resistance was determined. Estradiol treatments rendered plants susceptible to the pathogen, thus compromising the plant defense mechanisms. These results indicate that at low concentrations, estradiol functions as a biostimulant of growth, yield and primary metabolism of Arabidopsis. However, estradiol functions as a potential transcriptional regulator of the phenylpropanoid pathway genes in Arabidopsis, having a negative effect on the phenylpropanoid and flavonoid biosynthetic pathways.

关键词： Plant Ecology Plant Physiology Plant Host-Pathogen Interactions

Alleviation of Drought Stress in Arabidopsis thaliana by 17β-Estradiol Application

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American Journal of Plant Sciences 2016年第14期7卷 2072-2086页

作者： pallavi upadhyay Camelia Maier Department of Biological Sciences Texas Woman’s University Denton Texas USA

Animal steroidal hormones, including estrogens, are being introduced into the agricultural soil and water supply from increased pharmaceutical and farm waste. Considering the current levels of xenoestrogen contamination of plant environments in view of the climate change induced drought conditions, this study was designed to understand the effect of estradiol (ES) application on Arabidopsis drought stress responses. Estradiol treatment (10 nM, 100 nM) of plants subjected to drought stress conditions by withholding water for 7 days resulted in increased tolerance to drought stress reflected in the significantly higher plant survival rates of 74% and 78%, respectively compared to control plants’ survival rates of 36% (no treatment) and 40% (mock treatment). Estradiol application significantly increased the content of glutathione, proline and H2O2 and significantly enhanced the transcription of the stress responsive genes GSTU3, GER5, HSP101, and HSP70b. A high concentration of ES (10 μM) did not protect plants against drought stress and proved to be toxic. These results provide new insight into the effect of ES on drought-stress responses in Arabidopsis with possible practical agricultural applications regarding the effect of environmental estrogens on crop plants.

关键词： Arabidopsis Drought Stress Glutathione H2O2 Proline Stress Genes Xenoestrogens

Continuous Mixed p-norm Control Scheme with Reweighted L_(0) norm Variable Step Size for Mitigating Power Quality Problems of Grid Coupled Solar PV Systems

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CSEE Journal of Power and Energy Systems 2023年第4期9卷 1394-1404页

作者： pallavi Verma Avdhesh Kumar Rachana Garg Priya Mahajan Delhi technological university DelhiDelhi 110085India.

In this paper,the performance of a two-stage three-phase grid coupled solar photovoltaic generating system(SPVGS)is analyzed by using a novel reweighted Lo norm variable step size continuous mixed p-norm(RLo-VSSCMPN)of a voltage source inverter(VSI)control *** efficacy of the system is determined by considering unbalanced grid voltage,DC offset,voltage sag and swell,unbalanced load and variations in solar ***-VSSCMPN is used for inverter control and it ex-tracts fundamental components of load current for generating the reference grid current with a faster convergence rate and lesser steady state *** the proposed control,harmonics in the grid current follows the IEEE-519 norm and the performance is also satisfactory under varying environmental/load *** power generated from SPvGS is transferred optimally using a DC-DC boost converter utilizing the incremental conductance(INC)maximum power point *** proposed system is simulated using MATLAB/Simulink 2018a and test results are verified experimentally using dSPACE1202 in the laboratory to ensure the validity of a novel proposed robust *** Terms-INC maximum power point tracker,power quality,reweighted LoVSSCMPN algorithm,solar PV generating system,total harmonic distortion,voltage source inverter.

关键词： INC maximum power point tracker power quality reweighted LoVSSCMPN algorithm solar PV generating system total harmonic distortion voltage source inverter.

Exposure to air pollutants in Vietnam:Assessing potential risk for tourists

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Journal of Environmental Sciences 2018年第11期30卷 147-154页

作者： pallavi Pant Whitney Huynh Richard E.Peltier Department of Environmental Health Sciences School of Public Health and Health SciencesUniversity of Massachusetts

Tourism can form an important component of a nation＇s GDP, and Vietnam is among the most visited countries in Southeast Asia. Most studies on personal exposure focus on the general population, or occupational cohorts with exposure to specific pollutants. However, short-term exposure to air pollutants while visiting regions with high levels of air pollution can lead to acute health effects. A personal exposure study was conducted across three cities in Vietnam to estimate exposure to particulate matter （PM2.5） and black carbon for tourists. Measurements were conducted during the wet season in 2014 in Ho Chi Minh City, Da Lat and Nha Trang using portable instrumentation. Average 24-hr PM2.5 and BC exposures were estimated as 18.9 ± 9.24 and 3.41 ± 1.33 μg/m3 and among the three cities, Ho Chi Minh was found to have the highest PM2.5 concentrations. Environmental tobacco smoke, commuting and street food stands were found to contribute to highest levels of exposure to PM2.s and BC across all cities.

关键词： Vietnam PM2.5 BC Exposure ETS Commute

Anticancer Activities of Plant Secondary Metabolites:Rice Callus Suspension Culture as a New Paradigm

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Rice science 2021年第1期28卷 13-30页

作者： Wusirika Ramakrishna Anuradha Kumari Nafeesa Rahman pallavi Mandave Department of Biochemistry Central University of PunjabBathindaPunjab 151001India Department of Biological Sciences Michigan Technological University1400 Townsend Drive HoughtonMichigan 49931USA Interactive Research School for Health Affairs Bharati VidyapeethPuneMaharashtra 411043India

Plant natural products including alkaloids,polyphenols,terpenoids and flavonoids have been reported to exert anticancer activity by targeting various metabolic *** biological pathways regulated by plant products can serve as novel drug *** natural compounds or their derivatives used for cancer treatment and some novel plant-based compounds which are used in clinical trials were *** suspension culture with secondary metabolites can provide a continuous source of plant pharmaceuticals without time and space *** research has shown that rice callus suspension culture can kill>95%cancer cells with no significant effect on the growth of normal *** role of candidate genes and metabolites which are likely to be involved in the process and their potential to serve as anticancer and anti-inflammatory agents were *** scale production of plant callus suspension culture and its constituents can be achieved using elicitors which enhance specific secondary metabolites combined with bioprocess technology.

关键词： plant metabolite cancer metabolism rice callus suspension culture cytotoxicity anticancer agent

Lycopene and male infertility

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Asian Journal of Andrology 2014年第3期16卷 420-425页

作者： Damayanthi Durairajanayagam Ashok Agarwal Chloe Ong pallavi Prashast Center for Reproductive Medicine Glickman Urological and Kidney Institute Cleveland Clinic Cleveland Ohio USA Faculty of Medicine MARA University of Technology Sungai Buloh Selangor Malaysia.

Excessive amounts of reactive oxygen species （ROS） cause a state of oxidative stress, which result in sperm membrane lipid peroxidation, DNA damage and apoptosis, leading to decreased sperm viability and motility. Elevated levels of ROS are a major cause of idiopathic male factor infertility, which is an increasingly common problem today. Lycopene, the most potent singlet oxygen quencher of all carotenoids, is a possible treatment option for male infertility because of its antioxidant properties. By reacting with and neutralizing free radicals, lycopene could reduce the incidence of oxidative stress and thus, lessen the damage that would otherwise be inflicted on spermatozoa. It is postulated that lycopene may have other beneficial effects via nonoxidative mechanisms in the testis, such as gap junction communication, modulation of gene expression, regulation of the cell cycle and immunoenhancement. Various lycopene supplementation studies conducted on both humans and animals have shown promising results in alleviating male infertility--lipid peroxidation and DNA damage were decreased, while sperm count and viability, and general immunity were increased. Improvement of these parameters indicates a reduction in oxidative stress, and thus the spermatozoa is less vulnerable to oxidative damage, which increases the chances of a normal sperm fertilizing the egg. Human trials have reported improvement in sperm parameters and pregnancy rates with supplementation of 4-8 mg of lycopene daily for 3-12 months. However, further detailed and extensive research is still required to determine the dosage and the usefulness of lycopene as a treatment for male infertility.

关键词： antioxidants lycopene male infertility oxidative stress reactive oxygen species sperm parameters

Air pollution and climate change impact on forest ecosystems in Asian region-a review

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Ecosystem Health and Sustainability 2022年第1期8卷 406-420页

作者： Saurabh Sonwani Sharfaa Hussain pallavi Saxena Department of Environmental Studies Zakir Husain Delhi CollegeUniversity of DelhiDelhiIndia Department of Environmental Science Tezpur UniversityTezpurIndia Department of Environmental Sciences Hindu CollegeUniversity of DelhiDelhiIndia

Forests are complex ecosystems comprising various trophic levels responsible for carrying out various biogeochemical processes and providing ecosystem ***,forests in Asia are doubly challenged by climate change and air *** rapidly changing air quality,with increasing concentration of greenhouse gases(GHGs),trace gases,volatile organic compounds(VOCs),and ozone(O_(3))also causes global warming leading to climate change,thus jointly creating a challenging condition for the forest *** impact on forest ecosystems of the two anthropogenic stressors,viz.,climate change and air pollution,requires global *** two stressors have been widely studied separately but their combined impact on the forest ecosystem has not been studied extensively,particularly in the Asian *** this review article,we attempt to explore the importance of interlinking air pollution and climate change impact on Asian forests,by studying the decline of different forest types as a background and markers of forest ecosystem *** main aim is to understand and summarise the past and ongoing research in this area and to facilitate researchers and policymakers to upgrade their research,policies,and management strategies in the area of integration of air pollution and climate change impact on forest ecosystems in the Asian region.

关键词： Air pollution climate change nutrient cycling forests degradation asia

Synthesis, DNA and Photocleavage Studies of Ru（ll） Polypyridyl Complexes： [Ru（dppz）（pyz）4]（ClO4）2 and [Ru（dppz）（dmpyz）4]（ClO4）2 Complexes

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Chinese Journal of Chemistry 2012年第7期30卷 1641-1646页

作者： pallavi,Ponuganti Nagababu,Penumaka Laxmareddy,Kotha Padmaja,Naishadham Satyanarayana,Sirasani Department of Chemistry Osmania UniversityHyderabad-500007Andhra PradeshIndia

In view of the growing interest for the synthesis of metal complexes and their interaction with DNA, we have synthesized and characterized two complexes containing ruthenium as metal center. The complexes are of the type [Ru（dppz）L4]（C104）2 where L are biologically important ligands such as pyrazole and dimethylpyrazole. The characterization of these complexes is done by 1 H NMR, 13C NMR, elemental analysis and mass spectroscopy. The interaction of these complexes with CT DNA was monitored and binding constants were determined using absorption and fluorescence spectroscopy. The mode of binding was found to be intercalative for both complexes and was determined using hydrodynamic viscosity studies. The complexes were further studied for photocleavage studies with supercoiled plasmid pBR322 DNA.

关键词： Ru(II) complexes fluorescence binding constants hydrodynamic viscosity supercoiled plasmid DNA pBR322

Posterior lamellar tarsorrhaphy in the early treatment of severe eyelid trauma/burns

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World Journal of Emergency Medicine 2022年第5期13卷 393-395页

作者： Neelam Pushker Deepsekhar Das Sujeeth Modaboyina pallavi Singh Sahil Agrawal Oculoplasty&Pediatric Ophthalmology Services Dr Rajendra Prasad Centre for Ophthalmic SciencesAll India Institute of Medical SciencesNew Delhi 110029India

In patients with lagophthalmos due to eyelid trauma,it is imperative to ensure adequate closure of the eye to protect the ocular *** it is difficult to surgically close eyelids by conventional methods of tarsorrhaphy,such as intermarginal suture tarsorrhaphy,Week’s tarsorrhaphy,and tongue-in-groove *** need intact eyelid tissues to perform these procedures and might not be possible in patients with severe lagophthalmos due to lost/damaged eyelid tissues either due to deficient length of tissues or increased tension at the wound site,which can result in surgical failure.[1]

关键词： trauma wound treatment

Optimization of Groundwater Pumping on Coral Islands Through the Application of Artificial Neural Network

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地学前缘 2009年第S1期16卷 19-20页

作者： pallavi Banerjee V.S.Singh National Geophysical Research Institute(CSIR)

The development and growing population has resulted in the increasing demand for potable water in tiny atolls of Lakshadweep group,off the western coast of *** recent years,the groundwater quality,in such atolls,has been deteriorated due to indiscriminate exploitation of groundwater to meet the *** arranging a sustainable supply of groundwater has become the most challenging task on these tiny atolls for the survival of human life. Groundwater floats in the form of thin lens,which

关键词： artificial neural network aquifer salinity groundwater draft coral islands Lakshad-weep