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exploring the electromagnetic shielding behavior of lanthanum doped calcium nanoferrites

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Journal of rare earths 2024年第11期42卷 2128-2136页

作者： e.Ahilandeswari K.Sakthipandi r.rajesh Kanna G.rajkumar B.Ganesh Babu S.Arunmetha Aslam Hossain P.Sakthivel V.rajendran M.Srinidhi raghavan Department of Physics SRM TRP Engineering College Department of electronics and Communication engineering M. Kumarasamy College of Engineering Department of Physics Easwari Engineering College Department of Mechanical engineering SRM TRP Engineering College Centre for Advanced energy Studies Department of Electronics and Communication EngineeringKoneru Lakshmaiah Education Foundation Smart Materials research Institute Southern Federal University Centre for Materials Science Department of PhysicsScience and HumanitiesFaculty of EngineeringKarpagam Academy of Higher Education Centre for Nanotechnology Academy of Maritime Education and Training (Deemed to be University) Department of Chemistry and Centre for Nano-Materials and Displays B.M.S. College of Engineering

The present study focuses on the synthesis and characterization of lanthanum(La3+)-doped calcium nanoferrites(CaLaxFe2-xO4:x=0.025,0.050,0.075 and 0.100) using the sonochemical *** techniques were employed to analyze the effect of La3+infusion,raman spectroscopy confirms the presence of active A1g,T2gand egmodes in the CaLaxFe2-xO4nanoferrite,indicating the formation of an active ferrite *** introduction of La3+doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating（3.23-3,57 eV）.At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric *** higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic *** M-H curve exhibits ferromagnetic behavior,with La3+-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/*** incorporation of La3+also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic ***,these CaLaxFe2-xO4nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.

关键词： Dielectric Magnetism Microwave absorption Nanoferrites rare earths Structural properties

Soil security and global food security

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Frontiers of Agricultural Science and engineering 2024年第2期11卷 297-302页

作者： David r.MONTGOMerY Department of earth and Space Sciences University of Washington townSeattleWA 98105USA

Over the course of the postglacial period has managed to add degrade a substantial portion of the world's potential agricultural land. The soil loss and degradation that has repeatedly impacted regional societies around the world resulted from agricultural practices that increased the physical loss of soil(erosion), reduced soil organic matter, changed p H(acidification) or salinity,and disrupted or altered communities of soil life. In the coming century, as continued soil degradation threatens global food security while the global population keeps rising it is imperative that farmers develop and adopt soilhealth building(regenerative) practices to solve a problem that has plagued societies throughout history. Growing evidence suggests that agricultural systems that combine cover crops, reduced tillage, and diverse crop rotations can reduce erosion, enhance soil health and rebuild soil organic matter to cultivate beneficial soil life and harvest both economic and environmental benefits. In the coming post-oil world, global food security would benefit from a global effort to promote soil restoration to help addresses the challenge of sustainably feeding the world, increase soil-based carbon sequestration,protect on-farm biodiversity and reduce off-farm water pollution. Because soil security sets a solid foundation for global food security, agricultural policies and subsidies should be reformed to encourage farmers to adopt regenerative,soil-building practices.

关键词： Agriculture soil security food security regenerative

A bacterial protein rhp-PSP inhibits plant viral proliferation through endoribonuclease activity

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Journal of Integrative Agriculture 2024年第6期23卷 1967-1978页

作者： Lijie Chen Qianze Peng Xiaohua Du Weixing Zhang Ju’e Cheng Shu’e Sun Deyong Zhang Pin Su Yong Liu Longping Branch College of BiologyHunan UniversityChangsha 410082China State Key Laboratory of Hybrid rice/Institute of Plant Protection Hunan Academy of Agricultural SciencesChangsha 410125China

Plant virus causes massive crop losses ***,there is currently no effective measure to control plant viral ***,we identify an antiviral protein rhp-PSP,produced by the bacterial rhodopseudomonas palustris strain *** this study,we discover that the antiviral activity of rhp-PSP relies on its endoribonuclease *** the arginine(r)residue at position 129 onto alanine(A)abolishs its endoribonuclease activity on coat protein(CP)rNA of tobacco mosaic virus(TMV),consequentially,compromises the antiviral activity of *** investigation demonstrates that,the mutant rhp-PSP^(r129A)is unable to form the homotrimer as the wild type,indicating the importance of quaternary junction for the endoribonuclease *** of rhp-PSP in Nicotiana benthamiana significantly enhances the resistance against TMV of seedlings,while expression of rhp-PSP^(r129A)did not,confirming that endoribonuclease activity is responsible for the antiviral activity of *** addition,foliar spray of rhp-PSP solution on tomato and pepper plants significantly reduces the disease index of viral diseases,indicating that rhp-PSP shows potential to develop antiviral agent in practice.

关键词： rhodopseudomonas palustris rhp-PSP tobacco mosaic virus endoribonuclease antiviral activity

Optimized CUDA Implementation to Improve the Performance of Bundle Adjustment Algorithm on GPUs

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Journal of Software engineering and Applications 2024年第4期17卷 172-201页

作者： Pranay r. Kommera Suresh S. Muknahallipatna John e. McInroy Department of electrical engineering and Computer Science University of Wyoming Laramie Wyoming USA

The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its performance by implementing the algorithm on GPUs. In the previous research work, “Improving Accuracy and Computational Burden of Bundle Adjustment Algorithm using GPUs,” the authors demonstrated first the Bundle Adjustment algorithmic performance improvement by reducing the mean square error using an additional radial distorting parameter and explicitly computed analytical derivatives and reducing the computational burden of the Bundle Adjustment algorithm using GPUs. The naïve implementation of the CUDA code, a speedup of 10× for the largest dataset of 13,678 cameras, 4,455,747 points, and 28,975,571 projections was achieved. In this paper, we present the optimization of the Bundle Adjustment algorithm CUDA code on GPUs to achieve higher speedup. We propose a new data memory layout for the parameters in the Bundle Adjustment algorithm, resulting in contiguous memory access. We demonstrate that it improves the memory throughput on the GPUs, thereby improving the overall performance. We also demonstrate an increase in the computational throughput of the algorithm by optimizing the CUDA kernels to utilize the GPU resources effectively. A comparative performance study of explicitly computing an algorithm parameter versus using the Jacobians instead is presented. In the previous work, the Bundle Adjustment algorithm failed to converge for certain datasets due to several block matrices of the cameras in the augmented normal equation, resulting in rank-deficient matrices. In this work, we identify the cameras that cause rank-deficient matrices and preprocess the datasets to ensure the convergence of the BA algorithm. Our optimized CUDA implementation achieves convergence of the Bundle Adjustment algorithm in around 22 seconds for the largest dataset compared

关键词： Scene reconstruction Bundle Adjustment Levenberg-Marquardt Non-Linear Least Squares Memory Throughput Computational Throughput Contiguous Memory Access CUDA Optimization

eco-toxicity and health risk assessment of polycyclic aromatic hydrocarbons in surface sediments of Burullus Lake in egypt

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China Geology 2024年第3期7卷 460-468页

作者： Hanan e Osman Mohamed H e el-Morsy Hazem T Abd el-Hamid Department of Biology Faculty of Applied ScienceUmm Al-Qura UniversityMecca 24382Saudi Arabia Deanship of Scientific research Umm Al-Qura UniversityMakkah 24372Saudi Arabia National Institute of Oceanography and Fisheries(NIOF) Cairo 11865Egypt Botany and Microbiology Department Faculty of ScienceAl-Azhar UniversityCairo 11651Egypt

Polycyclic aromatic hydrocarbons(PAHs)are ubiquitous environmental contaminants of growing concern due to their potential ecological and human health *** study presents a comprehensive assessment of PAHs contamination in the surface sediments of Burullus Lake,a vital and second largest delta lake in *** aim was to evaluate the eco-toxicity and potential health risks associated with the presence of these *** seven sediment samples were collected from various drains in the southern part of Burullus *** extraction method was employed to extract PAHs(16PAHs)from the sediment ***,target compounds were located using *** results showed that samples contained PAHs levels ranging from 0.038×10^(-6)to 0.459×10^(-6),which is considered heavily polluted by the european standard for PAHs ***,there was no apparent source of PAHs in the elKhashah drain or the Brinbal Canal,as HPLC found none of the *** most prevalent compound in sediment samples along the study area was *** diagnostic indices in the present study indicated that the hydrocarbons in the region originated from pyrolytic and man-made sources along the drains of Burullus *** principal component analysis(PCA)and diagnostic ratios revealed that coal combustion and pyrolytic sources were responsible for the PAHs contamination in the surface *** non-carcinogenic risk(HI),which is the product of the HQs for the adult and child populations,respectively,was *** values under 1,therefore,demonstrated that they had no carcinogenic effects on human *** and MeQs in the sediments of Burullus Lake do not have a cancer-causing impact on *** the safety of nearby wildlife,aquatic life,and people,all activities that raise petroleum hydrocarbon levels in Burullus Lake must be adequately regulated and *** to the ecological risk assessment,there is little chance that PAHs will be found

关键词： Polycyclic aromatic hydrocarbons Diagnostic indices Toxicity Delta lake sediment Burullus Lake Human health risk Aquatic ecosystem HPLC Coal combustion

A systematic review of urban terrorism literature: root causes, thematic trends, and future directions

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JOUrNAL OF SAFeTY SCIeNCe AND reSILIeNCe 2024年第3期5卷 249-265页

作者： Mirza, Muhammad Noor e. elahi rana, Irfan Ahmad Natl Univ Sci & Technol NUST Sch Civil & Environm Engn SCEE Dept Urban & Reg Planning Sect H 12 Islamabad Pakistan

Urban terrorism is a significant global concern, prompting extensive scholarly inquiry into its underlying causes and effects. However, a comprehensive literature review summarizing this body of knowledge is notably absent. Thus, this study seeks to address this gap by conducting a thorough examination of existing literature on terrorism, particularly focusing on urban contexts, to identify key patterns and recurring themes. The study identified 515 research articles using the keywords "urban" and "terrorism" through the Web of Science and Scopus databases. A bibliometric review was conducted, which included a historical background, author keywords, country and institution, citation, and co-citation analyses. The findings revealed an increase in the number of studies on urban terrorism following the 9/11 attacks in the United States, which accounted for the highest number of publications in the country. Most studies were conducted in government law, international relations, and urban studies. Keyword analysis revealed that counterterrorism, security, and disasters were more closely linked to terrorism. Thematic analysis identified six main themes related to urban spaces and terrorism: tourism, governance, resilience, public health, economy, security, and counterterrorism. This study emphasizes the importance of involving the public in counterterrorism efforts in addition to traditional approaches to addressing urban terrorism.

关键词： Urban terrorism War on terror Intentional hazards Counterterrorism resilient cities NeW-YOrK-CITY POSTTrAUMATIC-STreSS-DISOrDer SePTeMBer 11TH CrITICAL INFrASTrUCTUre NATIONAL MALL VIOLeNCe IMPACT WArFAre rISK WAr

Control of visible‑range transmission and refection haze by varying pattern size,shape and depth in fexible metasurfaces

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Frontiers of Optoelectronics 2024年第3期17卷 51-68页

作者： Avijit Maity Vaswati Biswas r.Vijaya Department of Physics Indian Institute of Technology KanpurKanpur 208016India Centre for Lasers and Photonics Indian Institute of Technology KanpurKanpur 208016India

Cost-efective soft imprint lithography technique is used to prepare fexible thin polymeric surfaces containing a periodic arrangement of nanodimples and nanobumps of sub-micron *** a single master mold of self-assembled colloidal crystal,metasurfaces with diferent depths and heights of patterns with a fxed pitch are possible,which makes the process inexpensive and *** metasurfaces are studied for their difuse and total transmission and refection spectra in the visible *** transmission haze and refection haze are calculated from the *** surface containing nanobumps of lesser pattern height result in higher values of refection and transmission haze than from surfaces containing nanodimples of much higher depth for the same *** haze is more dependent on the pattern depth or height and less dependent on the pitch of the ***-feld transmission profles measured in the same wavelength range from the patterned surfaces show that the scattering increases with the increase of the ratio of pattern depth/height to pitch,similar to the haze measurements conducted with a closed integrating *** profles show that the angular spread of scattered light in transmission is within 10°,explaining the reason for the relatively low transmission haze in all the patterned *** results confrm that the nanobump pattern gives higher transmission haze compared to nanodimple *** controlling the ratio of pattern depth/height to pitch of the features on these surfaces,both an increase in optical haze and a balance between total refection intensity and total transmission intensity can be achieved.

关键词： Metasurface refection haze Transmission haze Soft imprint lithography

rodent biology and ecologically based rodent management(eBrM)-25 years of progress through promoting multidisciplinary research

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Integrative Zoology 2024年第1期19卷 2-7页

作者： Grant r. SINGLeTON Lyn A. HINDS rhodes MAKUNDI Steven r. BeLMAIN Natural resources Institute University of Greenwich Kent UK CSIrO Health and Biosecurity Canberra ACT Australia African Centre of excellence for Innovative rodent Pest Management and Biosensor Technology Development Sokoine University of Agriculture Morogoro Tanzania Institute of Pest Management Sokoine University of Agriculture Morogoro Tanzania

“During rodent outbreak years in eastern Africa,lo-cally,more than 80%of the potential harvest may be lost,but even in non-outbreak periods,rodents cause chronic damage to crops….The pest rodent story in Africa in-volves several species embedded in a broad and variable landscape with highly variable densities.”(Leirs et al.2010).

关键词： damage crops

Jigsaw-Sketch: a fast and accurate algorithm for finding top-k elephant flows in high-speed networks

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Science China(Information Sciences) 2024年第4期67卷 113-130页

作者： Boyu ZHANG He HUANG Yu-e SUN Yang DU Dan WANG School of Computer Science and Technology Soochow University School of rail Transportation Soochow University

Finding top-k elephant flows in high-speed networks is one of the most fundamental network measurement tasks. It is more challenging than per-flow size estimation since the IDs and sizes of top-k flows must be tracked simultaneously. Most existing studies only record the IDs of a small number of elephant flows to fit their estimators in the extremely limited high-speed on-chip memory. However, these solutions need too many memory accesses when a packet arrives to track the elephant flows with high accuracy, which limits their practicability. Therefore, this paper proposes Jigsaw-Sketch, a new algorithm to find the top-k elephant flows with much fewer memory accesses while achieving high memory efficiency and accuracy. In this design, we propose a novel two-stage jigsaw storage scheme, which can capture the candidate top-k flows from massive network steams efficiently, and further find the top-k elephant flows with high memory efficiency and only a few memory accesses for each packet. extensive experimental results based on real network traces show that Jigsaw-Sketch improves the packet processing throughput by at least 86%, while achieving smaller memory footprints and higher accuracy compared to the SOTA.

关键词： sketch top-k network measurement elephant flow high-speed networks