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Do *** conditions at the state level predict the realized volatility of oil‑price returns?A quantile machine‑learning approach

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Financial Innovation 2023年第1期9卷 645-666页

作者： Rangan gupta Christian Pierdzioch Department of Economics University of PretoriaPretoria 0002South Africa Department of Economics Helmut Schmidt UniversityHolstenhofweg 85P.O.B.70082222008 HamburgGermany

Because the *** a major player in the international oil market,it is interesting to study whether aggregate and state-level economic conditions can predict the subse-quent realized volatility of oil price *** address this research question,we frame our analysis in terms of variants of the popular heterogeneous autoregressive realized volatility(HAR-RV)*** estimate the models,we use quantile-regression and quantile machine learning(Lasso)*** estimation results highlights the dif-ferential effects of economic conditions on the quantiles of the conditional distribution of realized *** weekly data for the period April 1987 to December 2021,we document evidence of predictability at a biweekly and monthly horizon.

关键词： Oil price Realized volatility Economic conditions indexes Quantile Lasso Prediction models

Prediction of vibrations induced by trains on line 8 of Beijing metro

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2010年第4期11卷 280-293页

作者： De-yun DING Shashank gupta Wei-ning LIu Geert LOMBAERT Geert DEGRANDE Sehool of Civil Engineering Beijing Jiaotong University Beijing 100044 China Department of Civil Engineering K. U Leuven B3001 Heverlee Belgium

This paper mainly discusses the problem of ground-borne vibrations due to the planned line 8 of Beijing metro which passes under the National Measurement Laboratory.A lot of vibration sensitive equipments are placed in the *** is therefore necessary to study the impact of vibrations induced by metro trains on sensitive equipments and important to propound a feasible vibration mitigation *** on the coupled periodic finite element-boundary element (FE-BE) method,a 3D dynamic track-tunnel-soil interaction model for metro line 8 has been used to predict vibrations in the free field induced by trains running at variable speeds between 30 km/h and 80 km/*** types of track structures commonly used on the Beijing metro network have been considered:(1) high resilience direct fixation fasteners,(2) Vanguard fasteners,(3) a floating slab track and (4) a floating ladder *** each of these track types,the vibration isolation efficiency has been *** results of the numerical study can be used to predict vibrations in nearby buildings and to decide upon effective vibration countermeasures.

关键词： Ground-borne vibrations Coupled periodic finite element-boundary element (FE-BE) method Track structure Vibration isolation efficiency

An Interacting Gauge Field Theoretic Model for Hodge Theory: Basic Canonical Brackets

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Communications in Theoretical Physics 2014年第6期61卷 715-728页

作者： R.Kumar S.gupta R.P.Malik Department of Physics Centre of Advanced Studies Banaras Hindu University DST Centre for Interdisciplinary Mathematical Sciences Faculty of Science Banaras Hindu University

We derive the basic canonical brackets amongst the creation and annihilation operators for a two(1 + 1)-dimensional(2D) gauge field theoretic model of an interacting Hodge theory where a u(1) gauge field(Aμ) is coupled with the fermionic Dirac fields(ψ andˉψ). In this derivation, we exploit the spin-statistics theorem, normal ordering and the strength of the underlying six infinitesimal continuous symmetries(and the concept of their generators) that are present in the theory. We do not use the definition of the canonical conjugate momenta(corresponding to the basic fields of the theory) anywhere in our whole discussion. Thus, we conjecture that our present approach provides an alternative to the canonical method of quantization for a class of gauge field theories that are physical examples of Hodge theory where the continuous symmetries(and corresponding generators) provide the physical realizations of the de Rham cohomological operators of differential geometry at the algebraic level.

关键词： continuous symmetries 2D QED with fermionic Dirac fields symmetry principles basic canoni-cal (anti)commutators creation and annihilation operators conserved charges as generators deRham cohomological operators Hodge theory

Beneficiation of coal using supercritical water and carbon dioxide extraction:sulfur removal

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International Journal of Coal Science & Technology 2021年第4期8卷 717-726页

作者： Matthew J.DeCuir Ram B.gupta Bhima Sastri Department of Chemical and Life Science Engineering Virginia Commonwealth UniversityRichmondVA 23284-3068USA Office of Fossil Energy U.S.Department of Energy19901 Germantown RoadGermantownMD 20874-1290USA

This work explores the use of carbon dioxide,water,and their mixtures as solvent for the precombustion beneficiation of raw coal without using any toxic mineral acids in the temperature range of 200-400℃.The fluid polarity,ionic constant,and supercritical point can be adjusted by H_(2)O/CO_(2)ratio and *** carbon dioxide to hydrothermal fluid also increases the ionization by forming carbonic *** with supercritical fluids have several benefits including enhanced mass transport,ease of separation and recycle,wide range of extractive capability and tunability,better inherent safety,and in the case of carbon dioxide and water-low cost.A semi-continuous extraction system was designed and built in which pressure,temperature and the relative flow rates of CO_(2)and H_(2)O can be *** powder is kept in a packed bed and the extraction is carried out at 143 bar *** sulfur as a model heteroatom,extractive efficiency is examined as a function of the temperature,fluid composition,fluid flow,and extraction *** results indicate that carbon dioxide,water,and supercritical water-carbon dioxide(ScWC)all can effectively extract about 50%of total sulfur from bituminous coal in 1 *** above 350℃decreased effectiveness,and extraction above the supercritical point of pure water caused hydrothermal *** extraction may provide necessary control to prevent organic dissolution while removing sulfur.

关键词： Coal Supercritical Sulfur Beneficiation Cleaning Extraction

Genealogy and phylogeography of Cyprinid fish Labeo rohita （Hamilton, 1822） inferred from ATPase 6 and 8 mitochondrial DNA gene analysis

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Current Zoology 2014年第4期60卷 460-471页

作者： Rupesh K. LuHARIYA Kuldeep K. LAL Rajeev K. SINGH Vindhya MOHINDRA Arti gupta Prachi MASIH Arvind K. DWIVEDI Rakhi DAS u. K. CHAuHAN J. K. JENA National Bureau ofFish Genetic Resources (ICAR) Lucknow- 226 002 UP India School of Environmental Sciences APS University Rewa- 486 003 MP India

ATPase 6/8 gene （842 bp） of mitochondrial DNA was sequenced in Labeo rohita samples （n = 253） collected from nine rivers belonging to four river basins; Indus, Ganges, Brahmaputra and Mahanadi. Analysis revealed 44 haplotypes with high haplotype diversity （Hd） 0.694 and low nucleotide diversity （π） 0.001. The within population variation was larger （83.44%） than among population differences （16.56%）. The mean Fsv value （0.166; P 〈 0.05） for overall populations revealed moderate level of genetic structuring in the wild L. rohita populations. The haplotype network presented a single clade for wild L. rohita population, from different rivers. Negative values for Fu＇s index （Fs）, mismatch distribution analysis indicated period of expansion in L. rohita population. The time after recent expansion was estimated for each population, between 0.042 to 0.167 mya. The pattern of Isolation by Distance （IBD） was not significant （r = -0.113, P 〈 0.287）, when all the sampling locations were compared （Mantel test）, however, when an outlier （Indus, Brahmaputra and Mahanadi） was removed from the whole population set, a clear positive correlation between pairwise Fsv and geographic distance （Km） was seen. The analysis of data demonstrated that ATPase6/8 gene polymorphism is a potential marker to understand genetic population structure of wild L. rohita existing in different rivers. The study identified population substructure in wild L. rohita with common ancestral origin [Current Zoology 60 （4）： 460--471, 2014].

关键词： Labeo rohita ATPase6/8 mtDNA Polymorphism Genetic Divergence India

Differential Effects of Butyric Acid on Mouse Skin Tumorigenesis

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Biomedical and Environmental Sciences 1997年第4期10卷 436-441页

作者： KRISHNAP·gupta N·K·MEHROTRA EnvironmentalCarcinogenesisLaboratory IndustrialToxicologyResearchCentre EnvironmentalCarcinogenesisL

We studied the effects of butyric acid (BA) on mouse skin tumorigenesis using chronicanimal bioassays. Topical application of BA immediately after each treatment with 12-0-te-t radecanoyl phorbol-13-acetate (TPA) promoter' inhi bi ted skint umors. The effect was depe n -dent on the dose of BA applied. BA showed no marked inhibitory effect on either skin tumorinitiation or complete tumorigenesis induced by dimet hyl benzant hracene (DMBA ). Si nce t u -mor promotion reportedly involves epigenetic events whereas tumor initiation or complete tu-morigenesis takes place through genetic pathways, it is Possible that BA exerts its antitumori-genic effects mainly by altering the epigenetic events responsible for tumor promotion. The re-sults of the study could further be used to study the mechanism of action and modification ofantitumorigenic effects of BA in combination with other substances

关键词： DMBA Differential Effects of Butyric Acid on Mouse Skin Tumorigenesis

Biotransformation,multifunctional recycling mechanism of nanostructures,and evaluation of the safety of nanoscale materials

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Particuology 2023年第11期82卷 76-86页

作者： Debjyoti Talukdar Parveen Kumar Benu Chaudhary Deepak Sharma Nishant Yadav Obaid Afzal Abdulmalik Saleh Alfawaz Altamimi Waleed Hassan Almalki Sami IAlzarea Imran Kazmi Ashutosh Pareek Gaurav gupta Madan Mohan gupta Department of Medical Research Armenian Russian International University“Mkhitar Gosh”YerevanArmenia Shri Ram College of Pharmacy KarnalHaryanaIndia Guru Gobind Singh College of Pharmacy YamunanagarHaryanaIndia Department of Pharmaceutical Technology SOMSAdamas UniversityBarasat-Barracpore RoadKolkataWest BengalIndia B.S.Anangpuria Institute of Pharmacy FaridabadHaryanaIndia Department of Pharmaceutical Chemistry College of PharmacyPrince Sattam Bin Abdulaziz UniversityAl Kharj11942Saudi Arabia Department of Pharmacology College of PharmacyUmm Al-Qura UniversityMakkahSaudi Arabia Department of Pharmacology College of PharmacyJouf UniversitySakakaAl-JoufSaudi Arabia Department of Biochemistry Faculty of ScienceKing Abdulaziz UniversityJeddahSaudi Arabia Department of Pharmacy Banasthali VidyapithBanasthali-RajasthanIndia School of Pharmacy Suresh Gyan Vihar UniversityJagatpura302017Mahal RoadJaipurIndia Department of Pharmacology Saveetha Dental CollegeSaveetha Institute of Medical and Technical SciencesSaveetha UniversityChennaiIndia uttaranchal Institute of Pharmaceutical Sciences Uttaranchal UniversityDehradunIndia School of Pharmacy Faculty of Medical SciencesThe University of the West IndiesSt.AugustineTrinidad and Tobago

Current evidence of concept analyses recommending nanotechnology for biomedical uses abounds in recent research. The area of biotechnology interfaces with nanostructures, reconfigures their composition, and alters their characteristics;which influences the dispersion of the particles, the biotransformation they cause, and their potential toxic effect. It is vital to link the idea of the lifecycle of nanostructures to the biological impacts and use methodologies to identify, estimate, and track the gradual bioprocessing of nanostructures in vivo, from a body-wide level to a nanoscopic size. This is necessary because understanding how nanostructures processing, degradation, persistence, and recycling predict potential exposure risks. The safe implementation of nanotechnology-based products in biomedical applications necessitates an extensive understanding of the recycling and transformations of nanomaterials in a living organism. Long-term fate in the body is crucial, as it governs potential environmental risks to human health. Strategies may be used to manage the long-term outcome of nanostructures in an organism since, in addition to composition, their design also affects how long they last and how easily they degrade. The lifespan of nanoparticles, a flexible and biocompatible category of nanostructures that have made it into clinical trials, is the subject of this article. Strategies may be used to manage the long-term outcome of nanoparticles in an organism since, in addition to composition, their design also affects how long they last and how easily they degrade. This review explained the safety of nanoscale materials, biotransformation, and the multifunctional recycling mechanism of nanostructures.

关键词： Nanostructure Nanoparticle Biotransformation Toxiceffect Environmental risk

Prediction of vibrations from underground trains on Beijing metro line 15

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Journal of Central South university 2010年第5期17卷 1109-1118页

作者：丁德云刘维宁 gupta S LOMBAERT G DEGRANDE G School of Civil Engineering Beijing Jiaotong University Department of Civil Engineering K.U.Leuven Beijing urban Engineering Design and Research Institute Co. Ltd

The impact of vibrations due to underground trains on Beijing metro line 15 on sensitive equipment in the Institute of Microelectronics of Tsinghua university was discussed to propose a viable solution to mitigate the *** the state-of-the-art three-dimensional coupled periodic finite element-boundary element(FE-BE) method,the dynamic track-tunnel-soil interaction model for metro line 15 was used to predict vibrations in the free field at a train speed of 80 km/*** types of tracks(direct fixation fasteners,floating slab track and floating ladder track) on the Beijing metro network were considered in the model. For each track,the acceleration response in the free field was *** numerical results show that the influence of vibrations from underground trains on sensitive equipment depends on the track *** frequencies above 10 Hz,the floating slab track with a natural frequency of 7 Hz can be effective to attenuate the vibrations.

关键词： vibration prediction underground trains coupled periodic FE-BE method track types

Machine learning-based discovery of vibrationally stable materials

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npj Computational Materials 2023年第1期9卷 2304-2309页

作者： Sherif Abdulkader Tawfik Mahad Rashid Sunil gupta Salvy P.Russo Tiffany R.Walsh Svetha Venkatesh Institute for Frontier Materials Deakin UniversityGeelongVIC 3216Australia ARC Centre of Excellence in Exciton Science RMIT UniversityMelbourneVIC 3001Australia Applied Artificial Intelligence Institute(A2I2) Deakin UniversityGeelongVIC 3216Australia Chemical and Quantum Physics School of ScienceRMIT UniversityMelbourneVIC 3001Australia

The identification of the ground state phases of a chemical space in the convex hull analysis is a key determinant of the synthesizability of *** material databases have been instrumental in exploring one aspect of the synthesizability of many materials,namely thermodynamic ***,the vibrational stability,which is another aspect of synthesizability,of new materials is not *** first principles approaches to calculate the vibrational spectra of materials in online material databases is computationally ***,a dataset of vibrational stability for~3100 materials is used to train a machine learning classifier that can accurately distinguish between vibrationally stable and unstable *** classifier has the potential to be further developed as an essential filtering tool for online material databases that can inform the material science community of the vibrational stability or instability of the materials queried in convex hulls.

关键词： materials stability vibrational