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Pedosphere 2024年第3期34卷 530-539页

作者： Daniel D.SAURETTE Asim BISwAS Richard J.HECK Adam w.GILLESPIE Aaron A.BERG School of Environmental Sciences University of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada) Ontario Ministry of Agriculture Food and Rural Affairs1 Stone Rd WestGuelph ON N1G 2Y4(Canada) Geography Environment&GeomaticsUniversity of Guelph50 Stone Rd EastGuelph ON N1G 2W1(Canada)

In digital soil mapping(DSM),a fundamental assumption is that the spatial variability of the target variable can be explained by the predictors or environmental *** to adequately sample the predictors have been well documented,with the conditioned Latin hypercube sampling(cLHS)algorithm receiving the most attention in the DSM *** advances in sampling design,a critical gap remains in determining the number of samples required for DSM *** propose a simple workflow and function coded in R language to determine the minimum sample size for the cLHS algorithm based on histograms of the predictor variables using the Freedman-Diaconis rule for determining optimal bin *** preprocessing was included to correct for multimodal and non-normally distributed data,as these can affect sample size determination from the *** on a user-selected quantile range(QR)for the sample plan,the densities of the histogram bins at the upper and lower bounds of the QR were used as a scaling factor to determine minimum sample *** technique was applied to a field-scale set of environmental covariates for a well-sampled agricultural study site near Guelph,Ontario,Canada,and tested across a range of *** results showed increasing minimum sample size with an increase in the QR *** sample size increased from 44 to 83 when the QR increased from 50% to 95% and then increased exponentially to 194 for the 99%*** technique provides an estimate of minimum sample size that can be used as an input to the cLHS algorithm.

关键词： bin width digital soil mapping normal distribution quantile range sampling design

Coupled Cu doping and Z-scheme heterojunction for synergistically enhanced tetracycline photodegradation

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Nano Research 2024年第7期17卷 5937-5948页

作者： Huidong Shen Chunming Yang Song Hong Leiduan Hao Liang Xu Alex w.Robertson Zhenyu Sun Country State Key Laboratory of Organic-Inorganic Composites College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shaanxi Key Laboratory of Chemical Reaction Engineering College of Chemistry and Chemical EngineeringYan’an UniversityYan’an 716000China Department of Physics University of WarwickCoventry CV 47ALUK

Semiconductor-based photocatalysis by utilizing solar energy for sustainable organic pollutant elimination has been a promising tactic to alleviate environmental ***,the development of robust and efficient photocatalysts to degrade organic pollutants still faces major challenges because of insufficient charge *** we design and fabricate a heterojunction consisting of copper,carbon-modified TiO_(2),and sulfur-doped g-C_(3)N_(4)nanosheets(i.e.,S-C_(3)N_(4)/Cu/C-TiO_(2)).The heterostructure affords a remarkable synergistic photocatalysis for tetracycline hydrochloride degradation,achieving an 82.6%removal efficiency within 30 min under visible light irradiation,about 15.4 and 7.3 times higher than that of S-C_(3)N_(4)and C-TiO_(2),*** superior performance is attributed to the synergy between Cu doping and the Z-scheme heterojunction,which not only enhances the interfacial electric field effect,facilitating charge separation,but also boosts the redox *** charge carrier transfer between Cu/C-TiO_(2)and S-C_(3)N_(4)follows a Z-scheme,as verified by trapping experiments,electron spin-resonance spectroscopy,and density functional theory ***,the tetracycline hydrochloride degradation pathways are enunciated by liquid chromatograph mass spectrometry *** work provides an effective approach for constructing high-performance photocatalysts that have potential in environmental remediation.

关键词： photocatalysis Cu doping Z-scheme heterojunction electrons and holes separation tetracycline degradation

Reduction of epinephrine in the lumbar spinal cord following repetitive blast-induced traumatic brain injury in rats

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Neural Regeneration Research 2024年第7期19卷 1548-1552页

作者： Shigeharu Tsuda Mustafa Golam Jiamei Hou Kevin K.w.wang Floyd J.Thompson Prodip Bose Brain Rehabilitation Research Center Malcom Randall VA Medical CenterNorth Florida/South Georgia Veterans Health SystemGainesvilleFLUSA Department of Anesthesiology College of MedicineUniversity of FloridaGainesvilleFLUSA Department of Emergency Medicine University of FloridaGainesvilleFLUSA Department of Neuroscience University of FloridaGainesvilleFLUSA Department of Neurology University of FloridaGainesvilleFLUSA

Traumatic brain inju ry-induced unfavorable outcomes in human patients have independently been associated with dysregulated levels of monoamines,especially epinephrine,although few preclinical studies have examined the epinephrine level in the central nervous system after traumatic brain *** has been shown to regulate the activities of spinal motoneurons as well as increase the heart rate,blood pressure,and blood flow to the hindlimb ***,the purpose of the present study was to determine the impact of repeated blast-induced traumatic brain injury on the epinephrine levels in seve ral function-s pecific central nervous system regions in *** three repeated blast injuries at 3-day intervals,the hippocampus,motor cortex,locus coeruleus,vestibular nuclei,and lumbar spinal cord were harvested at post-injury day eight and processed for epinephrine assays using a high-sensitive electrochemical detector cou pled with high-performance liquid *** results showed that the epinephrine levels were significantly decreased in the lumbar spinal cord tissues of blast-induced traumatic brain injury animals compared to the levels detected in age-and sex-matched sham *** other function-specific central nervous system regions,although the epinephrine levels were slightly altered following blast-induced tra u matic brain injury,they were not statistically *** results suggest that blast injury-induced significant downregulation of epinephrine in the lumbar spinal cord could negatively impact the motor and cardiovascular *** is the first repo rt to show altered epinephrine levels in the spinal cord following repetitive mild blast-induced traumatic brain injury.

关键词： balance blood flow cardiovascular system central nervous system epinephrine ischemic damage lumbar spinal cord muscle tone repeated blast spasticity traumatic brain injury

Deletion of Axin1 in aggrecan-expressing cells leads to growth plate cartilage defects in adult mice

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Genes & Diseases 2024年第4期11卷 149-151页

作者： Dan Yi Hongting Jin william w.Lu Chunxiang Zhang Guozhi Xiao Liping Tonag Di Chen Research Center for Computer-aided Drug Discovery Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China PFaculty of Pharmaceutical Sciences Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China The First College of Clinical Medicine Zhejiang Chinese Medical UniversityHangzhouZhejiang 310053China Department of Cardiology Basic Medicine Innovation Centerfor Cardiometabolic Diseases of Ministry of EducationInstitute of Cardiovascular ResearchThe Affiliated HospitalSouthwest Medical UniversityLuzhouSichuan 646000China School of Medicine Southern University of Science and TechnologyShenzhenGuangdong 518055China

In mammals,skeletal bone development begins at hyaline cartilage formation at the early embryonic stage.1Then osteoblasts from the periosteum,which are distributed surrounding the hyaline cartilage,build up compact bone to formdiaphysis and spongy bone known as primary ossification center.1 Next,osteoclasts from the hematopoietic system destroy spongy bone to generate a medullary cavity.

关键词： cartilage skeletal medullary

Ultraslow electron-phonon scattering and polaron formation in magnetite

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Journal of Materiomics 2022年第1期8卷 150-155页

作者： adrian Radoń DariuszŁukowiec Patryk włodarczyk Łukasiewicz Research Network-Institute of Non-Ferrous Metals Sowinskiego 5 St.44-100GliwicePoland Faculty of Mechanical Engineering Silesian University of TechnologyKonarskiego 18 a St.44-100GliwicePoland

The comprehensive analysis of AC electrical conductivity in magnetite was performed in order to find relations between the formation of polarons,phonons and conduction by a virtual free electron *** analysis performed here for the first time shows experimental data for the behavior of electrons for magnetite with the scattering time shifted to the GHz *** to our study,the DC electrical conductivity can be described by the virtual free electron gas model,and high frequency conductivity can be described by the combination of the Drude model for disordered materials and Jonscher's universal power *** observed peak at the imaginary part of AC conductivity was related to the scattering time of the electron-phonon *** interaction between electrons and thermally formed phonons results in the formation of large polarons,and these are responsible for high frequency conductivity in magnetite.

关键词： Magnetite Drude model Power law Electrical conductivity Virtual free electron gas

Three- and Four-Dimensional Generalized Pythagorean Numbers

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Advances in Pure Mathematics 2024年第1期14卷 1-15页

作者： Alfred wünsche Institute of Physics Humboldt University Berlin Germany

The Pythagorean triples (a, b | c) of planar geometry which satisfy the equation a2+b2=c2 with integers (a, b, c) are generalized to 3D-Pythagorean quadruples (a, b, c | d) of spatial geometry which satisfy the equation a2+b2+c2=d2 with integers (a, b, c, d). Rules for a parametrization of the numbers (a, b, c, d) are derived and a list of all possible nonequivalent cases without common divisors up to d2 is established. The 3D-Pythagorean quadruples are then generalized to 4D-Pythagorean quintuples (a, b, c, d | e) which satisfy the equation a2+b2+c2+d2=e2 and a parametrization is derived. Relations to the 4-square identity are discussed which leads also to the N-dimensional case. The initial 3D- and 4D-Pythagorean numbers are explicitly calculated up to d2, respectively, e2.

关键词： Number Theory Pythagorean Triples Tesseract 4-Square Identity Diophantine Equation

Convergence Phenomenon with Fourier Series of tg(x2)and Alike

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Advances in Pure Mathematics 2024年第7期14卷 556-595页

作者： Alfred wünsche Institut fr Physik Humboldt-Universitt Berlin Berlin Germany

The Fourier series of the 2π-periodic functions tg(x2)and 1sin(x)and some of their relatives (first of their integrals) are investigated and illustrated with respect to their convergence. These functions are Generalized functions and the convergence is weak convergence in the sense of the convergence of continuous linear functionals defining them. The figures show that the approximations of the Fourier series possess oscillations around the function which they represent in a broad band embedding them. This is some analogue to the Gibbs phenomenon. A modification of Fourier series by expansion in powers cosn(x)for the symmetric part of functions and sin(x)cosn−1(x)for the antisymmetric part (analogous to Taylor series) is discussed and illustrated by examples. The Fourier series and their convergence behavior are illustrated also for some 2π-periodic delta-function-like sequences connected with the Poisson theorem showing non-vanishing oscillations around the singularities similar to the Gibbs phenomenon in the neighborhood of discontinuities of functions. .

关键词： Gibbs Phenomenon Generalized Functions weak Convergence Chebyshev Polynomials of First and Second Kind Even and Odd Generating Functions for Chebyshev Polynomials Polylogarithms Completeness Relations

ACCURATE AND EFFICIENT IMAGE RECONSTRUCTION FROM MULTIPLE MEASUREMENTS OF FOURIER SAMPLES

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Journal of Computational Mathematics 2020年第5期38卷 797-826页

作者： T.Scarnati Anne gelb Air Force Research Laboratory WPAFBOH 45433USA Dartmouth College HanoverNH 03755USA

Several problems in imaging acquire multiple measurement vectors(MMVs)of Fourier samples for the same underlying *** recovery techniques from MMVs aim to exploit the joint sparsity across the measurements in the sparse *** is typically accomplished by extending the use of`1 regularization of the sparse domain in the single measurement vector(SMV)case to using`2,1 regularization so that the“jointness”can be accounted *** effective,the approach is inherently coupled and therefore computationally *** method also does not consider current approaches in the SMV case that use spatially varying weighted`1 regularization *** recently introduced variance based joint sparsity(VBJS)recovery method uses the variance across the measurements in the sparse domain to produce a weighted MMV method that is more accurate and more efficient than the standard`2,1 *** efficiency is due to the decoupling of the measurement vectors,with the increased accuracy resulting from the spatially varying *** by these results,this paper introduces a new technique to even further reduce computational cost by eliminating the requirement to first approximate the underlying image in order to construct the *** this preprocessing step moreover reduces the amount of information lost from the data,so that our method is more *** examples provided in the paper verify these benefits.

关键词： Multiple measurement vectors Joint sparsity weighted`1 Edge detection Fourier data

Segmentation of Images from Fourier Spectral Data

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Communications in Computational Physics 2009年第2期5卷 326-349页

作者： Anne gelb Dennis Cates Department of Mathematics and Statistics Arizona State UniversityTempeArizona 85287 USA

This paper designs a segmentation method for an image based on its Fourier spectral *** edge map is generated directly from the Fourier coefficients without first reconstructing the image in pixelated *** the internal boundaries of the edge map are not blurred by any(filtered)Fourier *** edge map is then processed with an edge linking segmentation *** include examples from magnetic resonance imaging(MRI).Our results illustrate some potential benefits of using high order methods in imaging.

关键词： Fourier coefficients edge detection segmentation