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Enhancement of Urinary Elimination of 3-Bromobenzanthrone Metabolites by Oral Supplementation of Ascorbic Acid in Guinea pigs

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Biomedical and Environmental Sciences 2004年第4期17卷 390-396页

作者： rAVINDrA p. singh rAJ kHANNA SUBHASH k. kHANNA MUkUL DAS Department of Biochemistry Lucknow University Lucknow-226001Department of Biochemistry Lucknow University Lucknow-226001Food Toxicology Laboratory Industrial Toxicology Research Centre Postal Box No. 80 M. G. Marg Lucknow-226 001 IndiaFood Toxicology Laboratory Industrial Toxicology Research Centre Postal Box No. 80 M. G. Marg Lucknow-226 001 India

Objective 3-Bromobenzanthrone (3-BBA), an anthraquinone intermediate dye, is extensively used in textile industry. Since, our prior studies have shown that 3-BBA caused significant depletion of ascorbic acid (AsA) levels, the effect of exogenous supplementation of AsA on the urinary elimination of 3-BBA metabolites was investigated. Method Guinea pigs were treated with single oral dose of 3-BBA (50 mg/kg b. wt.) in groundnut oil while another group was treated with single oral dose of 3-BBA (50 mg/kg b. wt.) along with 3 day prior and post oral supplementation of AsA. Control groups were either treated with groundnut oil or AsA alone. Urine from individual animals was collected, extracted and analysed on HpTLC. results The highest elimination of 3-BBA (75 mg) was found to be in 0-24 h urine fraction which decreased to 18 mg and 5 mg in the two subsequent 24 hourly fractions of urine. Exogenous supplementation of AsA increased the total urinary elimination of 3-BBA by almost 77%. A total of 10 fluorescent metabolites excluding the parent compound were eliminated in the urine of guinea pigs treated with 3-BBA. Densitometric scanning of chromatogram showed different peaks at rf 0.18, 0.22, 0.27, 0.34, 0.40, 0.48, 0.56, 0.66, 0.72, 0.80, and 0.95 which were eliminated and marked as urinary metabolite 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 respectively. AsA not only significantly enhanced the elimination of 3-BBA metabolites but also modified the pattern of metabolites drastically in 0-6 h, 6-24 h and 24-48 h urine fractions. Conclusion These results indicate that AsA may be useful in protecting the toxicity of 3-BBA by fascilitating the urinary metabolite(s) excretion of 3-BBA.

关键词： Ascorbic acid 3-Bromobenzanthrone Metabolites High performance thin layer chromatography

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Targeting DNA repair for cancer treatment: Lessons from pArp inhibitor trials

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Oncology research 2023年第4期31卷 405-421页

作者： DHANYA k.NAMBIAr DEEpALI MISHrA rANA p.singh Department of radiation Oncology Stanford University School of MedicineStanfordCA94305USA Cancer Biology Laboratory School of Life SciencesJawaharlal Nehru UniversityNew Delhi110067India Special Centre for Systems Medicine Jawaharlal Nehru UniversityNew Delhi10067India

Ionizing radiation is frequently used to treat solid tumors,as it causes DNA damage and kill cancer ***,damaged DNA is repaired involving poly-(ADp-ribose)polymerase-1(pArp-1)causing resistance to radiation ***,pArp-1 represents an important target in multiple cancer types,including prostate *** is a nuclear enzyme essential for single-strand DNA breaks *** pArp-1 is lethal in a wide range of cancer cells that lack the homologous recombination repair(Hr)*** article provides a concise and simplified overview of the development of pArp inhibitors in the laboratory and their clinical *** focused on the use of pArp inhibitors in various cancers,including prostate *** also discussed some of the underlying principles and challenges that may affect the clinical efficacy of pArp inhibitors.

关键词： pArp inhibitors Synthetic lethality DNA repair BrCA mutations

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Control of rock joint parameters on deformation of tunnel opening

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Journal of rock Mechanics and Geotechnical Engineering 2016年第4期8卷 489-498页

作者： Suman panthee p.k.singh Ashutosh kainthola T.N.singh Central Department of Geology Tribhuvan University Department of Earth Sciences Indian Institute of Technology Bombay

In this paper, stress behavior of shallow tunnels under simultaneous non-uniform surface traction and symmetric gravity loading was studied using a direct boundary element method（BEM）. The existing fullplane elastostatic fundamental solutions to displacement and stress fields were used and implemented in a developed algorithm. The cross-section of the tunnel was considered in circular, square, and horseshoe shapes and the lateral coefficient of the domain was assumed as unit quantity. Double-node procedure of the BEM was applied at the corners to improve the model including sudden traction changes. The results showed that the method used was a powerful tool for modeling underground openings under various external as well as internal loads. Eccentric loads significantly influenced the stress pattern of the surrounding tunnel. The achievements can be practically used in completing and modifying regulations for stability investigation of shallow tunnels.

关键词： Stress behavior Boundary element method(BEM) Shallow tunnels Eccentricity

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pyGWBSE:a high throughput workflow package for GW-BSE calculations

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npj Computational Materials 2023年第1期9卷 2127-2136页

作者： Tathagata Biswas Arunima k.singh Department of physics Arizona State UniversityTempe 85287 AZUSA

We develop an open-source python workflow package,pyGWBSE to perform automated first-principles calculations within the GW-BSE(Bethe-Salpeter)***-BSE is a many body perturbation theory based approach to explore the quasiparticle(Qp)and excitonic properties of *** approximation accurately predicts bandgaps of materials by overcoming the bandgap underestimation issue of the more widely used density functional theory(DFT).BSE formalism produces absorption spectra directly comparable with experimental *** package achieves complete automation of the entire multi-step GW-BSE computation,including the convergence tests of several parameters that are crucial for the accuracy of these *** is integrated with Wannier90,to generate Qp bandstructures,interpolated using the maximally-localized wannier *** also enables the automated creation of databases of metadata and data,including Qp and excitonic properties,which can be extremely useful for future material discovery studies in the field of ultra-wide bandgap semiconductors,electronics,photovoltaics,and photocatalysis.

关键词： automated python enable

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Intensification of photocatalytic decomposition of water by ultrasound

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Journal of Energy Chemistry 2018年第4期27卷 1183-1188页

作者： Arvind singh A.S.k.Sinha Department of Chemical Engineering and Technology Indian Institute of Technology (Banaras Hindu University)

photocatalysis of water with and without ultrasound was studied using rGO supported CdS catalyst utilizing visible light. A higher hydrogen production was observed when ultrasound was used. This is attributed to a faster removal of bubbles of hydrogen from the surface of photocatalyst due to the mechanical energy associated with ultrasound overcoming surface tension. It has been further reported that the rate of hydrogen production decreased with time due to reversible deactivation of catalyst. This has been attributed to decrease in rate of hydrogen desorption with time.

关键词： Hydrogen photocatalysis Ultrasound kinetics

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rock fragmentation control in opencast blasting

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Journal of rock Mechanics and Geotechnical Engineering 2016年第2期8卷 225-237页

作者： p.k.singh M.p.roy r.k.paswan Md.Sarim Suraj kumar rakesh ranjan Jha CSIr-Central Institute of Mining and Fuel research

The blasting operation plays a pivotal role in the overall economics of opencast *** blasting subsystem affects all the other associated sub-systems,***,transport,crushing and milling *** control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole,varying initiation practice in blast design and its effect on explosive energy release *** paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in *** mines use draglines and shoveledumper combination for removal of *** its pivotal role in controlling the overall economics of a mining operation,the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting *** an approach is very poor substitutes for accurate assessment of explosive and blasting *** one blasts were conducted with varying blast designs and charging patterns,and their impacts on the rock fragmentation were documented.A high-speed camera was deployed to record the detonation sequences of the *** efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

关键词： Opencast blast rock fragmentation Explosives performance Dragline efficiency Fragment size

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Chemical hardness-driven interpretable machine learning approach for rapid search of photocatalysts

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npj Computational Materials 2021年第1期7卷 1850-1862页

作者： ritesh kumar Abhishek k.singh Materials research Centre Indian Institute of ScienceBangaloreKarnataka 560012India

Strategies combining high-throughput(HT)and machine learning(ML)to accelerate the discovery of promising new materials have garnered immense attention in recent *** knowledge of new guiding principles is usually scarce in such studies,essentially due to the‘black-box’nature of the ML ***,we devised an intuitive method of interpreting such opaque ML models through SHapley Additive explanations(SHAp)values and coupling them with the HT approach for finding efficient 2D watersplitting *** developed a new database of 30992D materials consisting of metals connected to six ligands in an octahedral geometry,termed as 2DO(octahedral 2D materials)*** ML models were constructed using a combination of composition and chemical hardness-based features to gain insights into the thermodynamic and overall *** importantly,it distinguished the target properties of the isocompositional 2DO materials differing in bond connectivities by combining the advantages of both elemental and structural *** interpretable ML regression,classification,and data analysis lead to a new hypothesis that the highly stable 2DO materials follow the HSAB *** most stable 2DO materials were further screened based on suitable band gaps within the visible region and band alignments with respect to standard redox potentials using the GW method,resulting in 21 potential ***,HfSe_(2)and ZrSe_(2)were found to have high solar-tohydrogen efficiencies reaching their theoretical *** proposed methodology will enable materials scientists and engineers to formulate predictive models,which will be accurate,physically interpretable,transferable,and computationally tractable.

关键词： intuitive formulate visible

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Viscous cosmology in holographic dark energy with Granda–Oliveros cut-off

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Communications in Theoretical physics 2023年第2期75卷 144-156页

作者： Simran kaur C p singh Department of Applied Mathematics Delhi Technological UniversityBawana RoadDelhi-110042India

We study the effect of bulk viscosity on holographic dark energy(HDE)with Granda–Oliveros infra-red *** focus on a generalized form of the bulk viscous coefficient which successfully describes the present-day evolution of the *** observe that the model with bulk viscosity provides an elegant description of the early and late-time evolution of the *** constrain the model through the combined observational data of the Strong Lensing System(SLS),measurements of Hubble parameter,Type Ia supernova data of pantheon sample and local H_(0)measured by *** best-fit values obtained from two different combinations of data,we estimate the present value of Hubble’s constant H_(0)=71.567-0.848+1.448and H_(0)=69.197-1.924+1.563,the deceleration parameter q_(0)=-0.535-0.016+0.016and q_(0)=-0.536-0.016+0.016,and the equation of state w_(0)=-0.690-0.010+0.010and w_(0)=-0.691-0.011+0.011,*** HDE model with bulk viscosity exhibits the phase transition from decelerated epoch to accelerated epoch.A comparison of the model with the standardΛCDM model is discussed with the statefinder and cosmographic parameters.

关键词： viscosity holographic dark energy cosmology

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Tree species composition and diversity in montane forests of Garhwal Himalaya in relation to environmental and soil properties

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Journal of Mountain Science 2020年第12期17卷 3097-3111页

作者： Dinesh singh rAWAT p.TIWArI Sudipta kumar DAS J.k.TIWArI Department of Botany&Microbiology HNB Garhwal UniversitySrinagar(Garhwal)-246174UttarakhandIndia Central National Herbarium Botanical Survey of IndiaHowrah-711103West BengalIndia

The montane forests of Garhwal Himalaya were investigated for tree species composition and diversity in relation to environmental and edaphic variables.A stratified random sampling approach was adopted to collect the field data from each forest.A total of 39 tree species belonging to 31 genera and 23 families were recorded from the sampling area(6 forest stands ×10 plots in each).Lauraceae with 5 species was the largest family while Quercus(4 species) emerged as the largest ***-area curve(asymptote) predicted more species than the observed number of *** analysis has shown that the two Abies pindrow dominant forest stands had the highest similarity in tree species *** tree stem density ranged from 540-1170 ha-1,basal area 23.01-55.94 m^2 ha-1,ShannonWiener diversity index 1.69-2.49,evenness index0.42-0.74,beta diversity 0.40-0.82 and similarity index 0.17-0.54 in the six studied ***-way indicator species analysis(TWINSpAN) identified four distinct tree communities in the study area with Daphniphyllum himalayense,Abies pindrow,Quercus oblongata,and pinus roxburghii as indicator species of corresponding *** correspondence analysis(CCA) ascertained the TWINSpAN results and revealed the relation of tree species with environmental and edaphic *** phytosociological attributes of tree species varied from one forest stand to another;however,the tree species richness,density,and diversity peaked at intermediate elevation on the north *** reveal that tree composition and diversity in the montane forests of Garhwal Himalaya are influenced by both environmental(elevation and slope aspect)and soil variables(texture,water holding capacity,moisture content,available N,exchangeable p,and pH).This study will help in understanding the forest distribution across the western Himalaya,guiding the conservationists and policymakers in carrying out conservation-related management activities,designing the long-

关键词： Diversity Tree species Montane forests Soil properties Western Himalaya

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Variation in the Flaring potential of Different Sunspot Groups During Different phases of Solar Cycles 23 and 24

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research in Astronomy and Astrophysics 2024年第2期24卷 144-153页

作者： Abha singh Anurag Chaudhari Gyaneshwar Sharma A.k.singh Department of physics T.D.P.G.College Jaunpur-222002India Department of physics Banaras Hindu UniversityVaranasi-221005India

In this present study,we have analyzed different types of X-ray solar flares(C,M,and X classes)coming out from different classes of sunspot groups(SSGs).The data which we have taken under this study cover the duration of 24 yr from 1996 to *** this,we observed a total of 15015 flares(8417 in SC-23 and 6598 in SC-24)emitted from a total of 33780 active regions(21746 in SC-23 and 12034 in SC-24)with sunspot *** defined the flaring potential or flare-production potential as the ratio of the total number of flares produced from a particular type of SSG to the total number of the same-class SSGs observed on the solar *** we studied yearly changes in the flaring potential of different McIntosh class groups of sunspots in different phases of SC-23 and *** addition,we investigated yearly variations in the potential of producing flares by different SSGs(A,B,C,D,E,F,and H)during different phases(ascending,maximum,descending,and minimum)of SC-23 and *** are our findings:(1)D,E,and F SSGs have the potential of producing flares≥8 times greater than A,B,C and H SSGs;(2)The larger and more complex D,E,and F SSGs produced nearly 80%of flares in SC-23 and 24;(3)The A,B,C and H SSGs,which are smaller and simpler,produced only 20%of flares in SC-23 and 24;(4)The biggest and most complex SSGs of F-class have flaring potential 1.996 and 3.443 per SSG in SC-23 and 24,respectively.(5)The potential for producing flares in each SSG is higher in SC-24 than in SC-23,although SC-24 is a weaker cycle than SC-23.(6)The alterations in the number of flares(C+M+X)show different time profiles than the alterations in sunspot numbers during SC-23 and 24,with several peaks.(7)The SSGs of C,D,E,and H-class have the highest flaring potential in the descending phase of both SC-23 and 24.(8)F-class SSGs have the highest flaring potential in the descending phase of SC-23 but also in the maximum phase of SC-24.

关键词： (Sun:)sunspots-Sun flares-Sun activity-Sun magnetic fields-Sun filaments-prominences

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