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Facile synthesis of samarium and cerium doped double perovskite cobaltite with enhanced dielectric response

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Journal of Rare Earths 2024年第7期42卷 1317-1327页

作者： Yasir Abbas m.Kamran m.Anis-ur-Rehman Applied Thermal Physics Laboratory Department of PhysicsCOMSATS University Islamabad

The investigation of Sm-Ce doping on structure,conduction,and dielectric response of Bi2Ca2-2xSmxCexCoO6（x=0.000,0.025,0.050,0.075）(BCSCCO) are presented.All the specimens were synthesized by a facile synthesis technique named the co-precipitation route.X-ray diffraction（XRD）reveals that BCSCCO crystallizes into one phase with space group P21/m.The crystallite size,dislocation density,lattice parameters,lattice strain,unit cell volume,and bulk density were determined using XRD data.The structural properties of Bi2Ca2CoO6were examined using calculations based on the density functional theory.Theoretical and experimental values discrepancy is less than 1%.A scanning electron microscope was used for performing a micro structural analysis.The SEm images demonstrate the homogeneous distribution of grains with a range of sizes（0.054-0.090 μm）.The alternating current（ac）conductivity, dielectric permittivity,and tangent loss were also studied as a function of frequency（20 Hz-3 mHz） at different temperatures（100-500℃）.All synthesized samples were examined using nonlinear Debye's function to determine their spreading factor and relaxation time.The specimen with the lowest crystallite size（～23 nm） exhibits a high dielectric permittivity（～3.80×10～6）.The conduction mechanism was examined in the studied samples with the use of Jonscher's power law.The power law indicates that the BCSCCO（x=0.000,0.025） follows correlated barrier hopping,whereas the x=0.050and 0.075 compositions follow non-overlapping polaron tunneling.The studied specimen Bi2Ca1.90Sm0.050Ce0.050CoO6with the highest density（～5.65 g/cm3） displays a high electrical conductivity（-46.1 S/cm）.These findings correspond to those published for ceramics made from calcium cobaltite using solid-state reactions（5.0-26.0 S/cm）.

关键词： Bismuth calcium samarium cerium cobaltite (BCSCCO) Conduction mechanism Rare earths Spreading factor

Optimal Coordination of Transportable Power Sources and Repair Crews for Service Restoration of Distribution Networks Considering Uncertainty of Traffic Congestion

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Journal of modern Power Systems and Clean Energy 2024年第1期12卷 189-201页

作者： Zhao Shi Yan Xu Dunjian Xie Shiwei Xie Amer m.Y.m.Ghias Nanyang Technological University Singapore the School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China

This paper proposes a new method for service restoration of distribution network with the support of transportable power sources(TPSs)and repair crews(RCs).Firstly,a coupling model of distribution networks and vehicle routing of TPSs and RCs is proposed,where the TPSs serve as emergency power supply sources,and the RCs are used to repair the faulted lines.Considering the uncertainty of traffic congestion,the probability distribution of the travel time spent on each road is derived based on the Nesterov user equilibrium model,and a two-stage stochastic program is formulated to determine the optimal routings of TPSs and RCs.To efficiently solve the proposed stochastic mixed-integer linear program(mILP),a two-phase scenario reduction method is then developed to scale down the problem size,and an adaptive progressive hedging algorithm is used for an efficient solution.The effectiveness of the proposed methods and algorithms has been illustrated in a modified IEEE 33-bus system.

关键词： Service restoration distribution network traffic uncertainty transportable power source repair crew stochastic program

Cell-type resolved transcriptomic approaches for dissecting selective vulnerability in neurodgeneration

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Neural Regeneration Research 2024年第7期19卷 1411-1413页

作者： Caleb A.Wood Nicholas m.Tran Department of Neuroscience Baylor College of MedicineHoustonTXUSA Department of molecular and Human Genetics Baylor College of MedicineHoustonTXUSA

A common feature among neurodegenerative conditions is that ce rtain neuronal populations are selectively vulnerable to loss(Fu et al.,2018).By corollary,other neurons are selectively resilient,suggesting they may possess unique features that support their survival.U nderstanding the basis of neuronal resilience or vulnerability would provide a logical strategy to identify factors that could be targeted therapeutically.

关键词： selective targeted

Bird species present in urban parks are more colorful than urban avoiders:A test in the Argentinian Pampas

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Avian Research 2024年第1期15卷 22-26页

作者： Lucas m.Leveau Departamento de Ecología Genetica y EvolucionFacultad de Ciencias Exactas y NaturalesUniversidad de Buenos Aires-IEGEBA(CONICET-UBA)Intendente Güiraldes 2160Ciudad UniversitariaC1428EGABuenos AiresArgentina

Bird plumage color has been assessed as a possible trait driving the presence of bird species in urban areas.Although some species can see the ultraviolet(UV) spectrum,the mentioned studies did not take into account UV reflectance when characterizing bird plumage.This study aimed to use a recent database of the colorfulness in passerines that incorporated the UV spectrum to compare bird colorfulness and other traits between urban parks and rural areas in Central-East Argentina.Birds in urban parks were surveyed in 51 parks in 6 cities during breeding and non-breeding seasons.A list of Passeriformes species from parks was created,and a list of urban avoider species was created from the bibliography.Species traits were body mass,clutch size,migratory status,nesting site,diet and habitat breadth,and plumage colorfulness.A total of 85 species were detected in the regional pool,of which 30 species were detected in urban parks.Bird species present in urban parks were more colorful than bird species only present in rural areas.In addition,bird presence in urban parks was positively related to their regional frequency and diet breadth.moreover,urban presence was related to nesting on trees and buildings,whereas species not present in urban parks nested on the ground.The results obtained showed that bird color is significantly associated with presence of bird species in urban parks.

关键词： Avian Filter Phenotype Selection Ultraviolet

Enhanced Wolf Pack Algorithm (EWPA) and Dense-kUNet Segmentation for Arterial Calcifications in mammograms

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Computers, materials & Continua 2024年第2期78卷 2207-2223页

作者： Afnan m.Alhassan College of Computing and Information Technology Shaqra UniversityShaqra11961Saudi Arabia

Breast Arterial Calcification(BAC)is a mammographic decision dissimilar to cancer and commonly observed in elderly women.Thus identifying BAC could provide an expense,and be inaccurate.Recently Deep Learning(DL)methods have been introduced for automatic BAC detection and quantification with increased accuracy.Previously,classification with deep learning had reached higher efficiency,but designing the structure of DL proved to be an extremely challenging task due to overfitting models.It also is not able to capture the patterns and irregularities presented in the images.To solve the overfitting problem,an optimal feature set has been formed by Enhanced Wolf Pack Algorithm(EWPA),and their irregularities are identified by Dense-kUNet segmentation.In this paper,Dense-kUNet for segmentation and optimal feature has been introduced for classification(severe,mild,light)that integrates DenseUNet and kU-Net.Longer bound links exist among adjacent modules,allowing relatively rough data to be sent to the following component and assisting the system in finding higher qualities.The major contribution of the work is to design the best features selected by Enhanced Wolf Pack Algorithm(EWPA),and modified Support Vector machine(mSVm)based learning for classification.k-Dense-UNet is introduced which combines the procedure of Dense-UNet and kU-Net for image segmentation.Longer bound associations occur among nearby sections,allowing relatively granular data to be sent to the next subsystem and benefiting the system in recognizing smaller characteristics.The proposed techniques and the performance are tested using several types of analysis techniques 826 filled digitized mammography.The proposed method achieved the highest precision,recall,F-measure,and accuracy of 84.4333%,84.5333%,84.4833%,and 86.8667%when compared to other methods on the Digital Database for Screening mammography(DDSm).

关键词： Breast arterial calcification cardiovascular disease semantic segmentation transfer learning enhanced wolf pack algorithm and modified support vector machine

Emerging role of galectin 3 in neuroinflammation and neurodegeneration

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Neural Regeneration Research 2024年第9期19卷 2004-2009页

作者： Brian m.Lozinski Khanh Ta Yifei Dong Department of Clinical Neuroscience University of CalgaryCalgaryABCanada Deparment of Biochemistry Microbiology&ImmunologyUniversity of SaskatchewanSaskatoonSKCanada

Neuroinflammation and neurodegeneration are key processes that mediate the development and progression of neurological diseases.However,the mechanisms modulating these processes in different diseases remain incompletely understood.Advances in single cell based multi-omic analyses have helped to identify distinct molecular signatures such as Lgals3 that is associated with neuroinflammation and neurodegeneration in the central nervous system(CNS).Lgals3 encodes galectin-3(Gal3),aβ-galactoside and glycan binding glycoprotein that is frequently upregulated by reactive microglia/macrophages in the CNS during various neurological diseases.While Gal3 has previously been associated with non-CNS inflammatory and fibrotic diseases,recent studies highlight Gal3 as a prominent regulator of inflammation and neuroaxonal damage in the CNS during diseases such as multiple sclerosis,Alzheimer’s disease,and Parkinson’s disease.In this review,we summarize the pleiotropic functions of Gal3 and discuss evidence that demonstrates its detrimental role in neuroinflammation and neurodegeneration during different neurological diseases.We also consider the challenges of translating preclinical observations into targeting Gal3 in the human CNS.

关键词： Alzheimer’s disease Galectin 3 microglia multiple sclerosis neurodegeneration neuroinflammation Parkinson’s disease therapeutics

Solute transport and geochemical modeling of the coastal quaternary aquifer, Delta Dahab Basin, South Sinai, Egypt

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Acta Geochimica 2024年第1期43卷 16-39页

作者： Amira Samy mustafa Eissa Seham Shahen moustafa m.Said Rabab m.Abou-shahaba Division of Water Resources and Arid Land Department of HydrogeochemistryDesert Research CenterCairoEgypt Egypt Desalination Research Center of Excellence Desert Research CenterCairoEgypt Center for Water Supply Studies S&E-Physical&Environmental SciencesTexas A&M University Corpus ChristiCorpus ChristiUSA Department of Chemistry Faculty of Science(Girls)Al-Azhar UniversityYousef Abbas StrNasr CityP.O.Box:11754CairoEgypt

The wadi dahab delta is in a dry, arid coastal zone within Egypt’s south Sinai Peninsula’s eastern portion. The primary water source is the Quaternary coastal alluvial aquifer. The groundwater salinity varies from 890to 8213 mg/L, with a mean value of 3417 mg/L. The dissolved major ions have been used to calculate the seawater mixing index(SWmI) using a linear equation that discriminates the groundwater mostly affected by water–rock interaction(SWmI 1>) and other samples mixed with Seawater(SWmI mposition of groundwater for specifically chosen groundwater samples ranges from-0.645‰ to +5.212‰ for δ^(18)O and from-9.582‰ to + 22.778‰ for δ^(2)H, where the seawater represented by a Red Sea water sample(δ^(18)O + 1.64‰-δ^(2)H + 9.80‰) and reject brine water are considerably enriched the isotopic groundwater values. The geochemical NETPATH model constrained by the dissolved significant ions, isotopes, and the rock aquifer forming minerals as phases indicate the mixing percent with the seawater ranges from 9% to 97% of seawater from 91% to 3% of original recharge water. According to the SEAWAT 3-D flow models, seawater has penetrated the Northeastern Dahab delta aquifer, with the intrusion zone extending1500 m inland. The salt dissolution, upwelling of saline water, recharge from the upstream mountain block, and seawater encroachment are the primary aspects contributing to the deterioration of groundwater quality. These findings may have significance for effective groundwater withdrawal management in arid locations worldwide with similar hydrogeological systems.

关键词： Groundwater geochemistry Seawater intrusion Solute transport SEAWAT

Growth of RB Population in the Conversion Phase of Chlamydia Life Cycle

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Communications on Applied mathematics and Computation 2024年第1期6卷 90-112页

作者： Frederic Y.m.Wan Department of mathematics University of CaliforniaIrvineCA92697-3875USA

Upon infecting a host cell,the reticulate body(RB)form of the Chlamydia bacteria simply proliferates by binary fission for an extended period.Available data show only RB units in the infected cells 20 hours post infection(hpi),spanning nearly half way through the development cycle.With data collected every 4 hpi,conversion to the elementary body(EB)form begins abruptly at a rapid rate sometime around 24 hpi.By modeling proliferation and conversion as simple birth and death processes,it has been shown that the optimal strategy for maximizing the total(mean)EB population at host cell lysis time is a bang-bang control qualitatively replicating the observed conversion activities.However,the simple birth and death model for the RB proliferation and conversion to EB deviates in a significant way from the available data on the evolution of the RB population after the onset of RB-to-EB conversion.By working with a more refined model that takes into account a small size threshold eligibility requirement for conversion noted in the available data,we succeed in removing the deficiency of the previous models on the evolution of the RB population without affecting the optimal bang-bang conversion strategy.

关键词： Chlamydia Life cycle Optimal control maximal infectious spread Specie competitive survival

Finding my way: The role of dirigent proteins in lignin assembly

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molecular Plant 2024年第2期17卷 230-232页

作者： Dyoni m.Oliveira Igor Cesarino Department of Plant Biotechnology and Bioinformatics Ghent University9052 GhentBelgium VIB Center for Plant Systems Biology 9052 GhentBelgium Departamento de Botanica Instituto de BiocienciasUniversidade de Sao PauloRua do Matao277Sao Paulo 05508-090Brazil Synthetic and Systems Biology Center InovaUSPAvenida Professor Lucio Martins Rodrigues370SaoPaulo 05508-020Brazil

Lignin emerged around 450 million years ago in early tracheophytes and played a pivotal role in the colonization of terrestrial ecosystems by plants.This aromatic biopolymer provides mechanical strength to supportive tissues and hydrophobicity to water-transporting vasculature and acts as a physical barrier against herbivores and pathogens(Renault et al.,2019).The deposition of lignin in cell walls for proper cellular functionalization involves several molecular steps,including the tight regulation of tissue-or cell-type-specific expression of lignin biosynthetic genes,the biosynthesis of distinct lignin monomers and their transportation to the apoplast,and the polymerization of monomer radicals to produce tissue-or cell-type-dependent polymers with distinct physico-chemical properties.

关键词： properties. lignin walls