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Phytochemical analysis,antioxidant,acetylcholinesterase,andα-amylase inhibitors from Hippeastrum hybridum extract

Journal of Traditional Chinese medicine 2024年第3期44卷 496-504页

作者： Naila Sher mushtaq Ahmed nadia mushtaq Department of Biotechnology University of Science and Technology Bannu-KPK 28100Pakistan Department of Botany University of Science and Technology Bannu-KPK 28100Pakistan

OBJECTIVE:To investigate the effects of Hippeastrum hybridum(HH)as a free radical scavenger,and an inhibitor of the two enzymes i-e Alpha-amylase(α-amylase)and acetylcholinesterase(AChE).mETHODS:In this study,HH plant was preliminary analyzed for phytochemical screening and then tested for its antioxidant,anti-α-amylase,and anti-AChE efficiency via standard ***:Phytochemical analysis shows the existence of different compounds;while Coumarins and quinones were *** total phenolic,flavonoid,and tannins content were found to be(78.52±0.69)mg GAE/g,(2.01±0.04)mg RUE/g,and(58.12±0.23)mg TAE/g of plant extract respectively.28.02%±0.02%alkaloid and 2.02%±0.05%saponins were present in the HH *** HH extract showed the anti-oxidant property with IC50(50%inhibition)of(151.01±0.13)(HH),(79.01±0.04)(Ascorbic acid)for ferric reducing,(91.48±0.13)(HH),(48.02±0.11)(Ascorbic acid)against Ammonium molybdenum,(156.02±0.31)(HH),(52.38±0.21)(Ascorbic acid)against DPPH,136.01±0.21(HH),52.02±0.31(Ascorbic acid)against H_(2)O_(2),and 154.12±0.03(HH),(40.05±0.15)(Ascorbic acid)μg/mL against ABTS *** analysis indicated that HH caused a competitive type of inhibition ofα-amylase(V_(max)remained constant and Km increases from 10.65 to84.37%)while Glucophage caused the un-competitive type of inhibition i-e both Km and V_(max)decreased from40.49 to 69.15%and 38.86 to 69.61%*** K_(i),(inhibition constant);K_(I),(dissociation constant),K_(m),(michaelis-menten constant),and IC50 were found to be62,364,68.1,and 38.08±0.22 for HH and 12,101.05,195,34.01±0.21 for ***,HH causes an anon-competitive type of inhibition of AChE i-e Km remains constant while V_(max)decreases from 60.5%to74.1%.The calculated K_(i),K_(I),K_(m),and IC50 were found to be 32,36.2,0.05,and 18.117±***:From the current results,it is concluded that HH extract contains bioactive compounds,and could be a good alternative to controlling oxidant

关键词： Hippeastrum hybridum phytochemicals antioxidant alpha-amylase acetylcholinesterase

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Nonlinear Study on the mechanical Performance of Built-Up Cold-Formed Steel Concrete-Filled Columns under Compression

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Computer modeling in Engineering & Sciences 2024年第6期139卷 3435-3465页

作者： Oulfa Harrat Yazid Hadidane S.m.Anas Nadhim Hamah Sor Ahmed Farouk Deifalla Paul O.Awoyera nadia Gouider Civil Engineering Laboratory Faculty of TechnologyDepartment of Civil EngineeringBadji Mokhtar-Annaba UniversityP.O.Box 12Annaba23000Algeria Department of Civil Engineering Faculty of Engineering and TechnologyJamia Millia Islamia(A Central University)New Delhi110025India Civil Engineering Department University of GarmianKalar46021Iraq Department of Civil Engineering Harran UniversitySanliurfa63510Turkey Structural Engineering and Construction management Department Future University in EgyptNew Cairo11835Egypt Department of Civil Engineering Covenant UniversityOta112233Nigeria

Given their numerous functional and architectural benefits,such as improved bearing capacity and increased resistance to elastic instability modes,cold-formed steel(CFS)built-up sections have become increasingly developed and used in recent years,particularly in the construction *** paper presents an analytical and numerical study of assembled CFS two single channel-shaped columns with different slenderness and configurations(backto-back,face-to-face,and box).These columns were joined by double-row rivets for the back-to-back and box configurations,whereas they were welded together for the face-to-face *** built-up columns were filled with ordinary concrete of good *** element models were applied,using ABAQUS software,to assess mechanical performance and study the influence of assembly techniques on the behavior of cold-formed columns under axial *** approaches based on Eurocode 3 and Eurocode 4 recommendations for un-filled and concrete-filled columns respectively were followed for the numerical analysis,and concrete confinement effects were also considered per American Concrete Institute(ACI)standards for face-to-face and box *** obtained results indicated a good correlation between the numerical results and the proposed analytical methodology which did not exceed 8%.The failure modes showed that the columns failed due to instabilities such as local and global buckling.

关键词： Cold-formed steel built-up sections slenderness rivets welded axial compression analytical approaches confinement buckling

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Optimal combination of the correction model and parameters for the precision geometric correction of UAV hyperspectral images

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 173-184页

作者： Wenzhong Tian za Kan Qingzhan Zhao Ping Jiang Xuewen Wang Hanqing Liu College of mechanical and Electrical Engineering Shihezi UniversityShihezi 832000XinjiangChina Research Center for Space Information Engineering Technology Shihezi 832000XinjiangChina XPCC Division of National Remote Sensing Center of China Shihezi 832000XinjiangChina College of Information Science and Technology Shihezi UniversityShihezi 832000XinjiangChina

Nowadays,with the rapid development of quantitative remote sensing represented by high-resolution UAV hyperspectral remote sensing observation technology,people have put forward higher requirements for the rapid preprocessing and geometric correction accuracy of hyperspectral *** optimal geometric correction model and parameter combination of UAV hyperspectral images need to be determined to reduce unnecessary waste of time in the preprocessing and provide high-precision data support for the application of UAV hyperspectral *** this study,the geometric correction accuracy under various geometric correction models(including affine transformation model,local triangulation model,polynomial model,direct linear transformation model,and rational function model)and resampling methods(including nearest neighbor resampling method,bilinear interpolation resampling method,and cubic convolution resampling method)were ***,the distribution,number,and accuracy of control points were analyzed based on the control variable method,and precise ground control points(GCPs)were *** results showed that the average geometric positioning error of UAV hyperspectral images(at 80 m altitude AGL)without geometric correction was as high as 3.4041 m(about 65 pixels).The optimal geometric correction model and parameter combination of the UAV hyperspectral image(at 80 m altitude AGL)used a local triangulation model,adopted a bilinear interpolation resampling method,and selected 12 edgemiddle distributed *** correction accuracy could reach 0.0493 m(less than one pixel).This study provides a reference for the geometric correction of UAV hyperspectral images.

关键词： geometric correction hyperspectral images unmanned aerial vehicle(UAV) ground control point(GCP)

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Parallelization of frequency domain quantum gates:manipulation and distribution of frequency-entangled photon pairs generated by a 21 GHz silicon microresonator

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Advanced Photonics 2024年第3期6卷 60-69页

作者： Antoine Henry Dario A.Fioretto Lorenzo m.Procopio Stéphane monfray Frédéric Boeuf Laurent Vivien Eric Cassan Carlos Alonzo-Ramos Kamel Bencheikh Isabelle zaquine nadia Belabas Institut Polytechnique de Paris LTCI Université Paris-Saclay CNRS Centre for Nanosciences and Nanotechnology Weizmann Institute of Science STmicroelectronics SAS

Harnessing the frequency dimension in integrated photonics offers key advantages in terms of scalability, noise resilience, parallelization, and compatibility with telecom multiplexing *** ring resonators have been used to generate frequency-entangled states through spontaneous four-wave mixing. However, state-of-the-art integrated resonators are limited by trade-offs among size,spectral separation, and efficient photon pair generation. We have developed silicon ring resonators with a footprint below 0.05 mm2providing more than 70 frequency channels separated by 21 GHz. We exploit the narrow frequency separation to parallelize and independently control 34 single qubit-gates with a single set of three off-the-shelf electro-optic devices. We fully characterize 17 frequency-bin maximally entangled qubit pairs by performing quantum state tomography. We demonstrate for the first time, we believe, a fully connected five-user quantum network in the frequency domain. These results are a step towards a generation of quantum circuits implemented with scalable silicon photonics technology, for applications in quantum computing and secure communications.

关键词： frequency domain integrated photonics quantum gates quantum networks

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Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil m.Patange P.m.Dighe Sher Singh meena Abdullah GAl-Sehemi mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=*** hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared *** creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray *** occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> *** refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter *** crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice *** XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent *** nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's *** analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) *** morphology of the hexaferrites was analyzed from the FESEm profiles of the ferrite *** magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.m,and mossbauer spectroscopy,*** hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the *** substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity m?ssbauer spectroscopy

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Prevelance of Bovine Cysticercosis in Egypt and the Cysticidal Effect of Two Extracts Obtained from Balanites aegyptiaca and moringa oleifera on mice model Affected with T. saginata Cysticerci

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Open Journal of Animal Sciences 2024年第2期14卷 39-55页

作者： Omnia m. Kandil Noha m. F. Hassan Doaa Sedky Hatem A. Shalaby Heba m. Ashry nadia m. T. Abu El Ezz Sahar m. Kandeel mohamed S. Abdelfattah L. Ying Ebtesam m. Al-Olayan Parasitology and Animal Diseases Department Veterinary Research Institute National Research Centre Dokki Cairo Egypt Chemistry of Natural Compounds Department Pharmaceutical and Drugs Industries Research Institute National Research Centre Dokki Cairo Egypt Chemistry Department Faculty of Science Helwan University Cairo Egypt State Key Laboratory of Plateau Ecology and Agriculture Qinghai University Xining China College of Agriculture and Animal Husbandry Qinghai University Xining China Department of Zoology Collage of Science King Saud University Riyadh Saudi Arabia

The aim of the present study was to determine the prevalence of bovine cysticercosis in both cattle and buffloas, in Egypt and to assess the cysticidal efficacy of Balanites aegyptiaca fruits (B. aegyptiaca) and moringa oleifera seeds (m. oleifera) extracts in experimentally infected mice. The study detected the level of tumor necrosis factor (TNF-α) to monitor the immune and inflammatory responses of experimentally infected mice. Through meat inspection, a total number of 2125 male bovine, 2 to 5 years old, (1125 cattle and 1000 buffloes) were examined under the authority of Albsatine and Alwaraq official abattoirs in Cairo Governorate, Egypt covering the period extended from march 2022 to April 2023. The overall prevalence of the disease among bovine was 7.8% (6.31% of cattle and 9.5% of buffloes). Besides, B. aegyptiaca and m. oleifera extracts showed cysticidal activity in experimentally infected mice. A decrease in the numbers of cysticerci was found in all treated mice groups, and up to 88% reduction was achieved in the B. aegyptiaca-treated group;higher than that was recorded in both m. oleifera (72.23%) and albendazole-treated ones (80.56%). Postmortem findings proved that m. oleifera and B. aegyptiaca reduced cysticerci numbers comparable to a commercial anthelmintic. The study showed a significant decrease (P 0.001) in TNF-α levels after treatment with Balanites and moringa extracts, compared with the untreated control and the albendazole-treated groups.

关键词： Prevalence Balanites aegyptiaca moringa oleifera mice T. saginata Cysticerci

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Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency *** different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into ***,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss *** the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL *** parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse *** results show that considering the rubber viscoelasticity enhances the wave attenuation ***,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal *** 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

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Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount *** the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher ch

关键词： Semiconductor TiO_(2) Rare earths Congo red methylene blue Solar spectrum Photodegradation

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Nonlinear dynamic modeling of planar moving Timoshenko beam considering non-rigid non-elastic axial effects

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 479-496页

作者： m.ABBASI GAVARI m.R.HOmAEINEZHAD Faculty of mechanical Engineering K.N.Toosi University of TechnologyTehran 19991-43344Iran

Due to the importance of vibration effects on the functional accuracy of mechanical systems,this research aims to develop a precise model of a nonlinearly vibrating single-link mobile flexible *** manipulator consists of an elastic arm,a rotary motor,and a rigid carrier,and undergoes general in-plane rigid body motion along with elastic transverse *** accurately model the elastic behavior,Timoshenko’s beam theory is used to describe the flexible arm,which accounts for rotary inertia and shear deformation *** applying Newton’s second law,the nonlinear governing equations of motion for the manipulator are derived as a coupled system of ordinary differential equations(ODEs)and partial differential equations(PDEs).Then,the assumed mode method(Amm)is used to solve this nonlinear system of governing equations with appropriate shape *** assumed modes can be obtained after solving the characteristic equation of a Timoshenko beam with clamped boundary conditions at one end and an attached mass/inertia at the *** addition,the effect of the transverse vibration of the inextensible arm on its axial behavior is *** the axial rigidity,the effect makes the rigid body dynamics invalid for the axial behavior of the ***,numerical simulations are conducted to evaluate the performance of the developed model,and the results are compared with those obtained by the finite element *** comparison confirms the validity of the proposed dynamic model for the *** to the mentioned features,this model can be reliable for investigating the system’s vibrational behavior and implementing vibration control algorithms.

关键词： planar moving Timoshenko beam non-rigid non-elastic axial effect as-sumed mode method(Amm) nonlinear motion analysis

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Free vibration and buckling analysis of polymeric composite beams reinforced by functionally graded bamboo fbers

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 543-562页

作者： H.m.FEIzaBAD m.H.YAS Department of mechanical Engineering Razi UniversityKermanshah ***Iran

Natural fibers have been extensively researched as reinforcement materials in polymers on account of their environmental and economic advantages in comparison with synthetic fibers in the recent *** fibers are renowned for their good mechanical properties,abundance,and short cycle *** beams are one of the fundamental structural components and are susceptible to mechanical loads in engineering applications,this paper performs a study on the free vibration and buckling responses of bamboo fiber reinforced composite(BFRC)beams on the elastic *** different functionally graded(FG)layouts and a uniform one are the considered distributions for unidirectional long bamboo fibers across the *** elastic properties of the composite are determined with the law of *** Hamilton’s principle,the governing equations of motion are *** generalized differential quadrature method(GDQm)is then applied to the equations to obtain the *** achieved outcomes exhibit that the natural frequency and buckling load values vary as the fiber volume fractions and distributions,elastic foundation stiffness values,and boundary conditions(BCs)and slenderness ratio of the beam ***,a comparative study is conducted between the derived analysis outcomes for BFRC and homogenous polymer beams to examine the effectiveness of bamboo fibers as reinforcement materials,demonstrating the significant enhancements in both vibration and buckling responses,with the exception of natural frequencies for cantilever beams on the Pasternak foundation with the FG-◇fiber ***,the obtained analysis results of BFRC beams are also compared with those for carbon nanotube reinforced composite(CNTRC)beams found in the literature,indicating that the buckling loads and natural frequencies of BFRC beams are lower than those of CNTRC beams.

关键词： bamboo fiber free vibration buckling analysis functionally graded(FG)beam elastic foundation generalized differential quadrature method(GDQm)

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