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Journal of Environmental Sciences 2024年第2期136卷 313-324页

作者： Saibal Ghosh Sandip Mondal Jajati Mandal Abhishek Mukherjee Pradip Bhattacharyya Agricultural and Ecological Research unit Indian Statistical InstituteGiridihJharkhand 815301India School of Science Engineering&EnvironmentUniversity of SalfordManchester M54WTUK

Heavy metals from mica waste not only deteriorate the soil quality but also results in the uptake of metals in the *** present investigation was conducted to evaluate the effects of different fractions of metals on the uptake in rice,soil microbial and biochemical properties in mica waste-contaminated soils of Jharkhand,*** each active mine,soil samples were randomly collected at distances of100 m(zone 3).Sequential metal extraction was used to determine the fractions of different metals(nickel(Ni),cadmium(Cd),chromium(Cr)and lead(Pb))including water-soluble(Ws)and exchangeable metals(Ex),carbonate-bound metals(CBD),Fe/Mn oxide(OXD)bound metals,organically bound metals(ORG),and residues(RS).The Ni,Cr,Cd and Pb in rice grain were 0.83±0.41,0.41±0.19,0.21±0.14 and 0.17±0.08 mg/kg *** the variable importance plot of the random forest(RF)algorithm,the Ws fraction of Ni,Cr and Cd and Ex fraction of Pb was the most important predictor for rice grain metal ***,the partial dependence plots(PDP)give us an insight into the role of the two most important metal fractions on rice grain metal *** microbial and enzyme activity was significantly and negatively correlated with Ws and Ex metal fractions,indicating that water-soluble and exchangeable fractions exert a strong inhibitory effect on the soil microbiological parameters and enzyme activities.

关键词： Metal fractions Microbial parameters Mica waste soil Soil enzymes Rice Random forest

Jackson-type inequalities on high-dimensional spheres

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Science China Mathematics 2024年第11期67卷 2571-2586页

作者： Yeli Niu Feng Dai Department of Mathematics Shanghai Normal University Department of Mathematical and statistical Sciences University of Alberta

We study Jackson's inequality on high-dimensional spheres with respect to the modulus of smoothness defined via the rotation *** obtain a version of Jackson's inequality with a dimensionfree constant,extending Newman and Shapiro's well-known results in 1964 from the case of r = 1 and p = ∞ to more general *** results partially overcome the curse of *** also establish similar results on the equivalence of the K-functional and modulus of smoothness.

关键词： modulus of smoothness $K$-functional Jackson's inequality high-dimensional approximation

Appraisal of pollution and health risks associated with coal mine contaminated soil using multimodal statistical and Fuzzy-TOPSIS approaches

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 101-115页

作者： Sumit Kumar Sonali Banerjee Saibal Ghosh Santanu Majumder Jajati Mandal Pankaj Kumar Roy Pradip Bhattacharyya Agricultural and Ecological Research unit Indian Statistical InstituteGiridih815301India Department of Life and Environmental Sciences Bournemouth University(Talbot Campus)Fern BarrowPooleBH12 5BBUK School of Sciences Engineering & EnvironmentUniversity of SalfordSalfordM5 4QJUK School of Water Resource Engineering Jadavpur UniversityKolkata700032India School of Environmental Studies Jadavpur UniversityKolkata700032India

The present study assesses the concentration,probabilistic risk,source classification,and dietary risk arising from heavy metal(HMs)pollution in agricultural soils affected by coal mining in eastern part of *** of soil and rice plant indicated significantly elevated levels of HMs beyond the permissible limit in the contaminated zones(zone 1:PbSoil:108.24±72.97,CuSoil:57.26±23.91,CdSoil:8.44±2.76,CrSoil:180.05±46.90,NiSoil:70.79±25.06 mg/kg;PbGrain:0.96±0.8,CuGrain:8.6±5.1,CdGrain:0.65±0.42,CrGrain:4.78±1.89,NiGrain:11.74±4.38 mg/*** 2:PbSoil:139.56±69.46,CuSoil:69.89±19.86,CdSoil:8.95±2.57,CrSoil:245.46±70.66,NiSoil:95.46±22.89 mg/kg;PbGrain:1.27±0.84,CuGrain:7.9±4.57,CdGrain:0.76±0.43,CrGrain:8.6±1.58,NiGrain:11.50±2.46 mg/kg)compared to the uncontaminated zone(zone 3).Carcinogenic and non-carcinogenic health risks were computed based on the HMs concentration in the soil and rice grain,with Pb,Cr,and Ni identified as posing a high risk to human *** Carlo simulation,the solubility-free ion activity model(FIAM),and severity adjusted margin of exposure(SAMOE)were employed to predict health *** hazard quotient(HQ)values for Ni,Cr,Cd,and Pb were>1,indicating a significant non-carcinogenic ***(risk thermometer)results for contaminated zones ranged from low to moderate risk(CrSAMOE:0.05,and NiSAMOE:0.03).Fuzzy-TOPSIS and variable importance plots(from random forest)showed that Ni and Cr were mostly responsible for the toxicity in the rice plant,respectively.A self-organizing map for source classification revealed common origin for the studied HMs with zone 2 exhibiting the highest *** positive matrix factorization model for the source apportionment identified coal mining and transportation as the predominant sources of *** distribution analysis indicated higher contamination near mining sites as compared to distant sampling ***,this study will aid environmental scientists and policymakers controllin

关键词： Coal mine Free ion activity model Monto Carlo Simulation Pollution and Health risk Fuzzy-TOPSIS

Rational Schur Superalgebras

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Algebra Colloquium 2024年第2期31卷 209-220页

作者： Andrew Riesen Shun-Jen Cheng Department of Mathematical and statistical Sciences University of Alberta 1132489 Ave NWEdmontonAlbertaCanada 不详

We develop and study the generalization of rational Schur algebras to the super *** to the classical case,this provides a new method for studying rational supermodules of the general linear supergroup GL(m|n).Furthermore,we establish a Schur-Weyl duality result for rational Schur superalgebras and conclude that under certain conditions these objects will be semisimple.

关键词： Schur algebra supermathematics general linear supergroup

Dynamical behaviors of a constant prey refuge ratio-dependent prey-predator model with Allee and fear effects

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International Journal of Biomathematics 2024年第1期17卷 227-250页

作者： Soumitra Pal Pijush Panday Nikhil Pal A.K.Misra Joydev Chattopadhyays Department of Mathematics Institute of Science Banaras Hindu University Varanasi 221005India Department of Mathematical and statistical Sciences University of Alberta EdmontonAB T6G 2G1Canada Department of Mathematics Visva-Bharati Santiniketan 731235India Agricultural and Ecological Research unit Indian statistical Institute 203 B.T.RoadKolkata 700108India

In this paper,we consider a nonlinear ratio-dependent prey-predator model with constant prey refuge in the prey *** Allee and fear phenomena are incorporated explicitly in the growth rate of the prey *** qualitative behaviors of the proposed model are investigated around the equilibrium points in *** bifurcation including its direction and stability for the model is also *** observe that fear of predation risk can have both stabilizing and destabilizing effects and induces bubbling phenomenon in the *** is also observed that for a fixed strength of fear,an increase in the Allee parameter makes the system unstable,whereas an increase in prey refuge drives the system toward ***,higher values of both the Allee and prey refuge parameters have negative impacts and the populations go to ***,we explore the variation of densities of the populations in different bi-parameter spaces,where the coexistence equilibrium point remains *** simulations are carried out to explore the dynamical behaviors of the system with the help of MATLAB software.

关键词： Predator-prey system Allee effect fear effect prey refuge bifurcation population density

Enhancing statistical Infrastructure to Improve Economic Census Efficiency

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Proceedings of Business and Economic Studies 2024年第5期7卷 13-19页

作者： Jie Liang Liangshan County statistical Data Center Jining 272699Shandong ProvinceChina

With the continuous development of the economy and societal progress,the economic census,as an important aspect of national statistical work,is directly influenced by the quality of grassroots *** paper thoroughly discusses the importance of strengthening the statistical foundation to improve the efficiency of economic census work,analyzes the existing issues in current infrastructure and census processes,and proposes corresponding *** enhancing the professional training of grassroots statisticians,updating data collection technologies,and optimizing workflows,the aim is to significantly improve the accuracy and efficiency of the economic census,providing strong support for the healthy development of the national economy and informed decision-making.

关键词： Statistics Grassroots construction Economic census

Quantized Redshift and its Significance for Recent Observation

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Research in Astronomy and Astrophysics 2024年第9期24卷 156-166页

作者： Arindam Mal Sarbani Palit Christopher C.Fulton Sisir Roy Indian Space Research Organization Space Applications CentreAhmedabadIndia Indian statistical Institute CVPR UnitKolkataIndia Protostar Inc.15652 Carrousel DriveCanyon CountryCA 91387USA National Institute of Advanced Studies IISC CampusBangaloreIndia

With the recent observational evidence in extragalactic astronomy,the interpretation of the nature of quasar redshift continues to be a research *** high redshifts are being detected for extragalactic objects that are presumably very distant and young while also exhibiting properties that are characteristic of a more mature galaxy such as *** to Halton Arp and Geoffrey Burbidge,redshift disparities consist of an intrinsic component and are related to an evolutionary *** observed redshift periodicity at integer multiples of0.089 in log scale and Burbidge observed redshift periodicity at integer multiples of 0.061 in linear *** Singular Value Decomposition based periodicity estimation is known to be superior for noisy data sets,especially when the data contain multiple harmonics and overtones,mainly irregular in nature,we have chosen it to be our primary tool for analysis of the quasar-galaxy pair redshift *** have observed a fundamental periodicity of0.051 with a confidence interval of 95%in linear scale with the site-available Sloan Digital Sky Survey Data Release 7(SDSS DR7)quasar-galaxy pair data *** have independently generated quasar-galaxy pair data sets from both 2d F and SDSS and found fundamental periodicities of 0.077 and 0.089,respectively,in log scale with a confidence interval of 95%.

关键词： galaxies:distances and redshifts (galaxies:)quasars:absorption lines cosmology:observations

Analysis of heterogeneous networks with unknown dependence structure

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Acta Mathematica Sinica,English Series 2024年

作者： Fangmei Hou Jiaxin Liu Shaogao Lü Huazhen Lin Center of statistical Research and School of Statistics Southwestern University of Finance and Economics Nanjing Audit University

In multiple heterogeneous networks, developing a model that considers both individual and shared structures is crucial for improving estimation efficiency and interpretability. In this paper,we introduce a semi-parametric individual network autoregressive model. We allow autoregression and regression coefficients to vary across networks with subgroup structure, and integrate both covariates and node relationships into network dependence using a single-index structure with unknown links. To estimate all individual and commonly shared parameters and functions, we introduce a novel penalized semiparametric approach based on the generalized method of moments. Theoretically, our proposed semiparametric estimator for heterogeneous networks exhibits estimation and selection consistency under regular conditions. Numerical experiments are conducted to illustrate the effectiveness of the proposed estimator. The proposed method is applied to analyze patient distribution in hospitals to further demonstrate its utility.

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Cholesterol-induced deformation of the gramicidin A channel inhibiting potassium ion binding and transport

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Chinese Physics B 2024年第5期33卷 696-702页

作者：肖盼曹宇朱瑾梁清 Center for statistical and Theoretical Condensed Matter Physics & Department of Physics Zhejiang Normal UniversityJinhua 321004China Zhejiang Institute of Photoelectronics & Zhejiang Institute for Advanced Light Source Zhejiang Normal UniversityJinhua 321004China

Gramicidin A(gA)is a kind of antibiotic peptide produced by bacillus brevis and it can dimerize across lipid bilayers to form a monovalent cation *** this work,we investigate the impact of cholesterol in the lipid bilayer on the binding of potassium ions with the gA channel and the transport of the ions across the *** results indicate that cholesterol can significantly influence the conformational stability of the gA channel and cause the channel deformation which inhibits the potassium ion binding with the channel and transport across the *** work provides some molecular insights into understanding of influence of lipids on the activity of gA channel in both model membranes and plasma membranes of intact cells.

关键词： gramicidin A lipid bilayer molecular dynamics interaction

Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 234-244页

作者： Jun-Yu Shen Bi-Wen Bao Li Zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China Key Laboratory of statistical Modeling and Data Analysis of Yunnan Province Yunnan UniversityKunming 650091China

Using an effective adiabatic index γ_(eff) to mimic the feedback of efficient shock acceleration,we simulate the temporal evolution of a young type Ia supernova remnant (SNR) with two different background magnetic field(BMF) topologies:a uniform and a turbulent *** density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic *** γ_(eff)is considered,we find that:(1) the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;(2) there exists more quasi-radial magnetic fields inside the shocked region;and (3) inside the intershock region,both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction,with γ_(eff)=1.1,they are amplified about 10–26 times more than those with γ_(eff)=5/*** in the angular direction,the total magnetic energy densities could be amplified about 350 times more than those with γ_(eff)=5/3,and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： methods:numerical ISM:magnetic fields ISM:supernova remnants magnetohydrodynamics(MHD)